I'm going to be testing both of these this year:

• Earthbox
• Gardener's Supply Company: Organic Tomato Success Kit

There are several homemade versions of this type of self-watering container floating around; here’s a nice one with instructions and videos:

http://earthtainer.tomatofest.com/

http://earthtainer.tomatofest.com/pdfs/EarthTainer-Construction-Guide.pdf

-- Andy