[Markulous]

I've used GFP and it's pretty good, tho' got to say that PS isn't too shabby (and no, never have found the 10% incremental enlarging that some suggest, to have any benefit). Depending on what you're enlarging (graphic, geommetrical, landscape, etc) determines the best algorithm.

Of course, you don't get something for nothing and there is a penalty to be paid with interpolating an image further upwards - but most cameras (Canon, Nikon, etc) have interpolated images anyway, so it's just taking it all a stage further.