Sledding, generally speaking, rules. Unfortunately, it only works in the winter time. Not so with the Slicer, which promises good times and grass stains.
What makes the Slicer so great is that it has detachable ice trays on the bottom. Simply pop them off, fill them with water, stick them in your freezer and you'll be all set to race down grassy hills like you're on snow. It looks amazingly fun and perhaps dangerous. [Product Page via Treehugger]