I have to say i love the 3-D text effects you can create, not to mention other 3-D objects you can open in Gimp and edit.Fantastic FREE software tool.Not sure if you can save in transparent png or gif, but i had no problem removing all the white bg with the magic wand tool.

After Sketchup


After Gimp


You can dl it here
http://sketchup.google.com/download/gsu.html

I've seen sketchup in action, it just isn't precise enough for me. I went to school for CAD for AutoCAD which was great but cost is criminal but I eventually settled on turboCAD which is a happy medium. Ok, I guess that was off topic but maybe worth the opinion if anyone else is in a quandary about which CAD software to use.

@Rod when u saved it what did u save it as? i cant open in in gimp

Although I'm not familiar with Sketchup, you can also get some interesting text effects with OpenOffice.org's Drawing application. It has something called Fontworks. There are several shapes and effects that can be applied while in Drawing, and the image can be exported in several formats including .png and .gif. I can't remember the name of the MS Office tool that this emulates - WordArt, perhaps?

It's not particularly precise, but it's also free and included in the OpenOffice package.

You have to save it as a 2D graphic, then it will auto save as a PNG file. =)