I got this water bottle at my local Kroger a little less than a year ago at the time of writing (January 2008). Made by Cool Gear International Inc., it claims to keep your drink colder. It uses a removable freezer unit in the shape of a tube with non-toxic freezer gel inside to keep your drink cold. You place the tube in the middle of the bottle and lock it in place with a cap at the top. Then you place the bottle top over the cap and twist it closed. You'll need to freeze the stick for at least 4 hours before use.
The bottle and cap is dishwasher safe but you have to wash the freezer tube by hand. The bottle is not microwave safe, and it's designed for ages 5 and up.
My bottle is a blue-green color that's also see-through material, so I can see the liquid and the tube inside. In my experience, the EZ-Freeze water bottle does keep your drink relatively cool for a long period of time. And the shatterproof claim is accurate - I once accidentally dropped it onto a wooded floor and it's still in tact. I mainly use it to try to accurately measure the amount of water I drink per day (I try to get 6 glasses a day total).