I'm not sure if this has been mentioned or not, but wides with 62mm or 52mm filter threads can easily be reversed for macro photography. I've had my 24/2.8 for about three years, but never tried reversing it until today! According to the BR-2A (reverse adapter) literature, the manual focus 24mm lens achieves an impressive 2.6X reproduction ratio (I don't have a 20mm, but it apparently reaches 3.4X). The biggest downside is that you can only focus by moving the whole camera back and forth, and if you're like me and you don't have a focusing stage, this means picking up your tripod up to move it a fraction of an inch while you try to keep your eye looking through the viewfinder. It's fun though.