Artweaver is an image editor that tries to simulate natural brush tools eg. chalk, charcoal, pencils. It supports common image formats such as BMP, GIF, JPEG, PCX, TGA, TIFF, PNG and PSD, in addition to its own format (AWD). Image editing functions includes selection, gradient, crop, fill, transparency, layers, effects (sharpen, blur, emboss, mosaic etc.).
A pro version is also available with additional features.