Ok, so this isn't my whole lighting kit, but it is an idea I came up with today, so I figured I'd share it. Since I started reading Strobist, I've always thought that one of the coolest things about lighting with small flashes is the free access to every color gel they make. I started picking out the gels I used most often and extending them with tape tabs and velcro to attach them to the flash, but I didn't like the idea of having to pick just a few colors to carry with me. Plus, I couldn't come up with any really convenient and compact way to carry them once I put the velcro on.
I thought of the idea of making some kind of gel holder like the ones they use in theatrical lights so I didn't have to cut the gels at all. After trying a few things, what worked best was just two strips of clear plastic with velcro at the ends that I could attach to the flash head, and then just slide the gel between them and the flash.
For carrying purposes, I just removed the plastic pins that held the gel swatch books together and replaced them with the kind of binder rings you would use to organize index cards. This way, I can just use and reuse the already-hole-punched gels without cutting them or changing them in any way. Plus, I can order them in any way I want, and throw away all the sample diffusion and reflector materials that just get in the way. Don't know why I didn't come up with this earlier.
Photo taken with SB-28 bounced off ceiling and triggered with 4ch ebay remote.