Adam wrote about this free sippy cup from Juicy Juice back in July of '08, but it appears that the offer is still alive and kicking. Some might wonder why a grown man with no children would sign up for this offer, but my answer is quite simply: it's the perfect size for rum & cokes with all the spill-proof protection that an inebriated person needs! Although if you do have kids, you'll want to make sure you don't accidentally swap each other's cups. That has disaster written all over it.
For a limited time offer, they have a free water bottle available as well.
[thanks to Betty for letting me know this was still available!]