Thought I start a thread where we could post cool tools and mods.

Yesterday I got a bike with a 10 speed record (the new 10 speed not the old one we all love) bottom bracket and rear cassette. The tool for removing this is a BBT-5 from park, but I had an old FR-1 that worked on the rear cassette just fine and with a lot of big drilling to enlarge the axle hole to fit over the bottom bracket stud I got the bottom bracket out smooth as pie as well!

I want to invent a "funny bike spline" universal tool someday.

I'm thinking of making a seat-post removal tool.
I'd use the rails of an old seat, and weld some handlebars to it, I can use those for more leverage, and it can be clamped to a stand.

I made my own headset cup remover a while back. Just took a steel pipe, cut four slits about two inches long, and spread the tabs. It doesn't work great, because the tabs are different sizes becasue I didn't cut straight, so sometimes the smaller tabs get pushed back in. Not a huge problem, just bend them back in, but eventually all this bending back and forth will cause it to break.