1. Fotoflexer
Crop; resize; rotate; flip; hue/saturation/lightness; contrast; various Photoshop-like effects.
2. Photobucket
Crop; resize; rotate; flip; hue/saturation/lightness; contrast; various Photoshop-like effects.
3. Photoshop Express
Requires free registration; 2 GB storage; crop; rotate; resize; auto correct; exposure correction; red-eye removal; retouching; saturation; white balance; sharpen; color correction; various other effects
4. Picnik
“Auto-fix”; rotate; crop; resize; exposure correction; color correction; sharpen; red-eye correction.
5. Pic Resize
Resize; crop; rotate; brightness/contrast; conversion; other effects.
6. Snipshot
Resize; crop; enhancement features; exposure, contrast, saturation, hue and sharpness correction; rotate; grayscale.
7. rsizr
For quick cropping and resizing.
8. EasyCropper
For quick cropping and resizing.
9. Pixenate
Enhancement features; crop; resize; rotate; color effects.
10. Splashup
Requires free registration; Flash-based interface; resize; crop; layers; flip; sharpen; blur; color effects; special effects.
11. FlauntR
Requires free registration; resize; rotate; crop; various effects.
12. LunaPic
Similar to Microsoft Paint; many features including crop, scale and rotate.
13. Wiredness
Resize; crop; exposure correction; rotate; flip; color effects; brightness/contrast; sharpen; blur.
14. 72photos
Requires free registration; 200 MB storage space; rotate; crop; effects including blur; picture enhancement.
15. myImager.com
Resize; crop; rotate; flip; brightness/contrast, color adjustment; sharpen; blur; various effects; line drawing; border.
16. Cellsea
Resize; crop; rotate; flip; blur; sharpen; color effects; various effects.
17. VicImager
resize; flip; mirror; rotate; brightness/contrast, color adjustment; conversion; various effects.
18. Onlinephototool.com
Similar to Microsoft Paint; many features including resize, crop, and filters..
19. Online Image Editor
File conversion; crop; rotate; flip; color correction; border.
20. Piccyfix
Rotate; flip; crop; colorize/tint; brightness; contrast; various effects; border; resize.
21. pixer.us
Resize; crop; rotate; flip; brightness & contrast; saturation; color effects; blur, sharpen.
22. FixPicture.org
Resize; crop; rotate; mirror effect; adjust brightness, contrast; various effects including sharpen and grayscale.
source : http://www.arnanmax.com/2009/09/22-free-online-photo-editing-tools/