HTML/rich text email signatures in iOS? My work (Exchange) email signature has text formatting and a photo in it, as I'm sure many do. Does anyone know of a way to enable Apple Mail like signature customization in iOS? 

My iPhone is jailbroken, so if you have a jailbreak solution that works I'm good with that.
There's a JailBreak Tweak called Mail Enhancer that does exactly what you want. It's $4.99 in the BigBoss repository, and there's another one called SIGnify for $1.50 in the ModMyi repo. They both allow you to have signatures with HTML formatting, but the more expensive one has many more features that make the Mail.app much more usable.