i would have to recommend one of the higher end models from the Canon Pixma MP range...it's not 'technically' portable, but i would say it is...as all the flaps (printer trays, cassette tray, lcd monitor, controls, etc.) all fold flat, making it just like a box. I use it on location work for events when I want to sell prints then and there, the model I have is the mp600, they are ultra inexpensive now-a-days, I think mine was £150 about 6months ago, but I'd opt. for a higher up model just because! I actually prefer to use it for prints that clients order through me of their images (over having them done at a lab) as it's fast, nice quality, and does a good A4, as long as you get the high quality glossy photo paper (made by Canon and few others)! very cost effective too, inks last a long while (even when printing super fine quality), and are inexpensive, i think my last set was about £35 for them all (as there are 5 separate ink tanks). another benefit is that you can just slot the memory card into the reader and use the on-screen controls (easy scroll wheels and other various button controls) to select the image, crop, etc. without need of a pc.
