Where is the Paint equivalent for Macs ?

I am not sure if I am being really dense but does anyone out there know of a good ( ideally free/cheap ) image editor for Macs ? Let me explain what I want to make it clearer.

My main requirement is for something to re-touch/edit small graphic images, typically screen grabs, in order to use on this and my other web sites. Typically this involves erasing small parts of a screen grab that I don’t want.

So far most of the apps I can find fall into one of three categories, big bloated Photoshop style replacement apps ( Gimp etc ), simple image manipulation apps ( Imagewell, Xee ) for re-sizing/rotating etc or vector graphics type apps such as Inkscape.

Is there a small OSX app that meets my needs or does everyone out there in Mac Land have full copies of Adobe Photoshop ?

Please help me out here !

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