I recently had the opportunity to share a bathroom with my nephew. Hmm. There are mysterious things in the bathroom of a 17 year old!! Most I chose not to ask about but the plugged drain in the shower definitely needed attention so I brought it up. That sent us searching for solutions. My sister was determined to find an environmentally friendly fix. I'd like to share our research with HouseTalk Show listeners.
This introductory article from the DoItYourself web site was a good starting point. I thought the suggestions at the end to keep the problem from reoccurring were very good.
Here's a good pictorial if you have a "Lift and Turn" drain from eHow.
If the above methods don't work and you feel the need for a drain cleaner, there are environmental friendly options.
Baking Soda
Eco-Friendly Drain Cleaners article from About.com
Pamela
a HouseTalk fan