The following picture was taken with a 2 mega pixal cell phone. It consists
of 9 individual shots stitched together with 3 free software programs
(Huggin,Autopano and Enblend). Huggin is the main program witch calls
Autopano to stitch the files together and then calls Endblend to smooth
out the stitches. If you look closely you can see the stitch line. A friend
did this for me and I have not tried the tools but
plan on it. So use at your own peril.
Hugin -
hugin - Panorama photo stitcher
autopano -
Panorama software photo stitcher: Autopano Pro Home - Autopano Pro Website
enblend -
Enblend 
Linear Mode
