grocery bags

ever since reading about how ireland's basically eliminated plastic bags there, the sleepy environmentalist/idealist in me has been yawning, stretching, and mulling it over... the example of a government actually enacting large-scale positive change without too much pain is the exciting part, but the little mental voice that says couldn't i? is back. (watch out, next thing you know i'll be back to my old vegetarian hippie ways...)

these aren't the cheapest, but they look neat. anybody have any experience habitually using cloth shopping bags? recommendations on features that wouldn't be apparent to a newbie but become awfully apparent after a few weeks hauling the things around?