The Energon Pub

http://www.maj.com/cgi-bin/gallery.cgi?i=145287

(Not sure if I ever posted them on this Transformer site...)

Magmaclaw and Icebuster were Razorclaw and Rockbuster.
A disassembly and switch of parts, requiring only a screwdriver.
(Actually, I used a heatgun to ever so slightly soften the ass hinge, so a needle could be poked through to pop out the metal rod holding it on).

I swear, it was like these two figures were MADE to be swapped.

Razorclaw was orange with a blue shell.
Rockbuster was aqua with a red shell.
A creative nature merely took it's course.

If you've got the time and the bots you can do the same sort of thing with Unicron and Black Unicron. Black Unicron came with Orange clear parts including his hand. The "Orange" Unicron came with Purple clear parts more suited for Black Unicron.