Lazyweb: Cheap phone service?

So it looks like work is going to give me an iPhone (yay) but that they won't transfer my current number, which used to just be my personal number and that I've had for years, to it (boo). It's probably a good wake up call -- if the number is important to me (which it is), I should have it under my own control.

Here's what's important to me:

  • I want to maintain my current phone number -- it's on business cards and headshots and so on and with the kind of odd jobs I do it's good for 4-year-old contacts to still be able to find me.
  • I get texts as well as calls (so some sort of voice-mail only service probably won't work for me).
  • I don't really want to carry two phones.

I'm not sure there's a perfect solution, but so far the best I can come up with is to port the number to a cheap service and then forward the number to my new work phone (so that I don't have to carry two phones) and then just check texts on the old number every now and then. So I guess I'm looking for cheap cell phone service that lets me call forward and, hopefully, on which texts aren't too pricey. Any better suggestions or do you know of a good service like I've described before I just start pricing it out everywhere?

Update: I went with Virgin Mobile. We'll see how this works out.