The current version (2.02):

It has 29 different "effects" in all.  Ones you would recognize: invert, flip vertical/horizontal, overlay one picture on another, adjust colors/brightness, and the rest are pretty much just things I made up.

Most effects have settings, so you can put your "feel" into it. 

It has at least 10 effects that I am almost certain no other programs can do.

It can read most file types (GIF, JPEG, TIFF, PNG, PICT, Photoshop formats, BMP, Targa, ICO, CUR, Sunraster, XBM, XPM, and PCX)

It can write to those same file types (so, if you have bmps and want to convert them to the much more space efficient format "jpg", it can do that)