First real alternative to Photoshop launched... and it's free!

I use GIMP and it does the job perfectly.

May be that I am more used to working with GIMP for the past 8-9 years.

GIMP handles all editing tasks as that of photoshop such as masks, layers, warp, levels curves, noise removal, vignetting, crop, resize and several preset effects/filters, that too for free.

Paint.Net is another free option that does all things easily.