>>93473
That's a good question. I think my most specialized tool is maybe like my cassette tool or crank puller or something.

I try not to buy the really niche stuff like wheel truing tool or rear hanger alignment tool. Better to just take that to a shop.

I would really like a massive breaker bar as the bottom bracket on my trainer bike is totally fused to the frame and there's no fucking way I'm getting it off