Here we have a tutorial on making a planter out of a single pallet:
And here are some inspirational examples compiled by a DIYer who calls herself the Backyard Diva (click the link and be amazed): PALLET CREATIONS GALORE!
Depending on your own personal style, you can express yourself and your home/garden as someone who is modern, rustic, whimsical, classic, cutesy, playful, artistic... and you can impress your IKEA- and Pottery Barn-obsessed friends with your own brand of self-taught craftsmanship.
The best part? You can often find pallets FOR FREE. They are usually lying around the loading docks of grocery/hardware/supply stores, and just about anywhere that transports supplies and goods into a building. Just be sure to ask before taking a few, and the workers might even thank you for taking the "clutter" off their hands.
HAPPY PALLET-HUNTING! And be sure to post pics of your finished pallet projects!