I’ve found some great little projects with which to use found materials or your own trash and turn it into something beautiful!
At DIYNetwork, we have recycled planters, using paint cans, cinder blocks or old jello molds.

Instructables (love that site) has a simple and free self-watering planter which you can also do with 2L soda bottles.
Here’s an example of the 2L at groovygreen.com.

And last but not least, a fun video on a self-watering 5 gallon pail