Auto-resizing of images

I found a need for a tool the other day - blogsome has a 300k size limit on image file uploads. Wouldn’t it be nice to be able to have image files automatically resized/recompressed so they are smaller than a certain size…I wonder if this is possible. I’d like to see this feature in ecto. Rather than just presets, make a ‘smart action’, that automatically chooses image size/compression to make the image fit in a certain amount of data.