If by that you mean "I use Linux but can't stand GIMP" then Pinta is pretty good as a simple photo editor. More advanced than Paint but not as unfriendly as GIMP. If you're familiar with Paint.NET on Windows then you'll feel right at home.
I also used Pinta but don't remember what worked for me, Pinta or Krita. I use one of them mostly for making icons transparent. I just thought I'd also drop JSPaint here, that was the first one I found.