As the title says!

It doesn't even have to be a game you've done a full run for. Maybe it's a run you find interesting, but you don't think others find it interesting.

...Or it can even be simply a run that's actually very fun, but it's just not as fun as the others you've done.

As for mine:
I'd once practiced a bit of Pokemon Battle Revolution, and well, it definitely wasn't a game for me. I might still do it one day, but I'm more likely to take up a different game from the series than that one.

There's also that run of getting married in Rune Factory 1 I did recently, which is a lot of nothing across nearly 2 in-game years. I liked doing it, but I can't imagine most folks would see much in it. Heck, even if I did like it, it's not a run I'm likely to do on a regular basis.

I've done a ton of speedruns of construct 3 games, which includes some runs of games that are beyond boring. If you don't know what construct 3 is, it's a program designed to be easy to help kids learn to code, similar to scratch. Some people can make really good games with it (you may have heard of "There is no game" which was made with it), but just like scratch there are thousands of terrible games too.

I also speedran mc classic one time and lost all of my braincells. anyone who runs that garbage is a masochist

Mission: Escape from Island
the run literally is hold W and spam Space to jump up hills.
oh yeah you might have tho pres M1 to shoot couple times

A while back I did a few speedruns of an obscure game called Monument Simulator (http://ostracodfiles.com/monument/main.html). Not only is the speedrun uninteresting, but the entire game is also (intentionally) uninteresting. It's literally just mining stone out of the ground and building a rectangle. Nonetheless, I speedran building a 10x10 monument in under 6 minutes which you can watch here:

I hope you'll be able to see why I have not tried requesting this game to SRC.

I don't think I'd ever be able to make a run of a game I find boring. None of my speedrun games I've done less than at least twice (at the very minimum), so I wouldn't know.

But I've tried to learn speedruns of various games, and some I just gave up for not fitting my style.

This is probably a example of one of those games that shouldn’t be on src as it’s essentially a visual novel. But like man don’t do this game unless you want Carpal Tunnel Syndrome and that isn’t cool:

And yes, I cut the video short cuz I definitely screamed.

Pikmin 3 Deluxe Category Extensions: Bingo Battle. The most boring category in Category Extensions where you had to kill the one Pikmin you had 12 times as quickly as possible. Other Categories such as 6 Fruits are way more fun to grind and try out.
EDIT: I never did that Run again. My first try was already WR so who cares.

Ninja Roy: Infinite 100 levels https://www.speedrun.com/ninja_roy_infinite/run/y6rrenjy it gets very repetitive.

Despicable Forces Quarantine%.
The goal is to stay at the first level for as long as you can.

Haven't attempted it yet, but Speed Run 4 100% is something i believe nobody will do for a long time.
The main currency to buy cosmetics and everything in the game are called "gems". There are a lot (A LOT.) of cosmetics to buy, adding up to a total of 4,843,783 gems to purchase all Dances, Songs, and Trails in the game.
Roblox Games have the oppurtunity to give the player badges in the game, and this is done throughout all of Speed Run 4. The hardest/longest ones to get will be to beat the game a total of 30 times, and to beat the game with all 5 "modes" equipped. Modes can be obtained by collecting stars at the end of every level in every dimension (30 levels, 7 times) and can be activated in level 0. Some are quite trivial, but to beat the game with all 5 you must endure 30 levels of constant spinning, upside-down controls and camera, reversed and zombie-infested levels, where you are also not allowed to die due to the ragequit mode. Then, to get the remaining badges, die in certain levels once and then go to the start, activate zombie, mirror, and ragequit mode. The modes can be used in this run because they give you extra gems per level. Go to level 21 in the Birchock dimension, and beat it (????) times. The reason for this is that Birchock level 21 has a skip that allows you to complete it in about 4 seconds consistently. So you'd need to grind that and then you'd have finished the run. My estimate is about 50 hours, but it will probably go a lot higher due to human error. I'm gonna attempt it sometime this summer if nobody else does by then.

As awesome and cool as this may sound, consider it will probably take about 40 or more hours to just grind that one level over and over. At least.

I did a three hour story mode speedrun. Most don’t find it interesting but I really liked it, and I’m attempting a faster time asap

Mario & Luigi: Dream Team -- "Glitchless Crash%".
Okay, so, a crash is a glitch, but you can not use glitches to crash the game. This is basically "do the Glitchless speedrun until you reach this point then perform this obscure crash".

The category as long as the Any%, and Any% is 4 hours long. (My sum of best is a 3:56:2x and my PB is a 4:04:40)
You basically have to reach Mount Pajamaja, get Side Drill, then go to Mushrise Park and Side Drill into the camera block. It crashes the game and the speedrun ends.

I have done this speedrun twice, the first time was on a Chinese translation ROM hack and the second time was on my PAL cartridge.

I also have done a single speedrun of "Glitched Glitchless Crash%", where you effectively do the exact crash from Glitchless Crash% but you're allowed to use glitches. That turns the run from 4 hours long to 2 hours long, lol.

I have an idea for an even more obscure category though, now... "Glitchless Battle Crash%".
Basically, you have to crash the game without the use of glitches, but the crash must happen within a battle. And what known ways are there to crash the game in battles?
That's right! The final boss, as soon as he dies! Basically, as soon as the final boss' head's HP reaches zero, his arms' stats completely unload (I checked through watching the RAM Values with CTRPF). If you try to attack something that doesn't exist, the game crashes.

There is an attack, called Bye-Bye Cannon, which attacks 12 times. First, 6 times, and if the enemy that is attacked within the first 6 hits dies, it then targets another enemy for another 6 hits. If it doesn't die, it just continues attacking the selected enemy.

Maybe you'll see where I'm going with this... But... If you kill the final boss' head within the first 6 hits, the game tries to have you attack the arms. Wait a minute... The arms don't have stats! Beep boop, the game crashed!

"Glitchless Battle Crash%" would be ~6-7 minutes shorter than Glitchless. The explanation for the crash turned out to be more interesting than I thought, though, lol. Maybe the runs aren't that uninteresting...? I might actually do this ridiculous category. lol