My contribution for those who are into working with photos:

1) Irfanview - freeware from a guy in Austria (his name is Irfan). Very good for batch conversions: any format to any other, resizing, renaming, color --> B&W etc. Works fast too. http://www.irfanview.com/

2) Helicon - not free but worth it. From a Russian genius, it converts and corrects just about everything you could ever wish for - distortions, color correction, sharpening, fringing, hot pixel noise, etc. Check it out at
http://helicon.com.ua/pages/

3) Rasterbator - sounds like something you have hide from your mother, but really - it´s a cool free program from some guys in Finland to make HUGE posters in a dot matrix output from any photo onto multiple sheets of A4 size paper...as many as you want...as big as you want (no matter how small the data size!). As they say on the site: "Pimp your room"
http://arje.net/raterbator

For your general amusement, here´s a rasterbated image in my corridor