Geckos don't have shells, but Gekkos will -- and it looks like T-Mobile is going to be serving up an unprecedented level of customization for its latest Sidekick. Hiptop 3 is showing mockups of what appears to be T-Mobile's shell creation site, a special little place on the internets where users will be able to design their own Gekko (aka Gecco, aka Sidekick 2008, aka "please just release this thing already") skins, which in turn will likely be outsourced to Skinit for manufacture. Considering the Sidekick's line wild, crazy, and creative target demographic, it seems like a great idea and a potential gold mine of secondary revenue for the carrier. Who's going to be the first with an Engadget shell, hmm?