I have been meaning to learn some sort of image manipulation tool for quite some time. I have used the Gimp in the past when I want to scale something or convert images from one format to another but I have never had the time or inclination to sit down and learn enough of it to be reasonably confident.
I have just had a long weekend so I decided to learn it because like it or lump it, its a very handy tool in any web developers arsenal. I mainly do backend work but there are occasions when I envy the versatility of other web developers when putting together sites. If you want to have a look at the sort of stuff I mean have a look at the The Zen Garden. Some of the pages on that site are just divine.