Free image splicing software available?

I am trying to make some really wide perspective shots by stitching photos together and I want to know what you guys recommend is the best for doing such with 3 to 15MB files. I use a PC, not a Mac by the way.

You can get a free trial of PTGUI (google it). I find it to be a pretty easy to use but advance stiching program. Also if you like the program isn't much to buy.

I have not tried this one, but I've read that it is well received:

http://www.cs.ubc.ca/~mbrown/autostitch/autostitch.html

Let us know what you think,
Tim