This is a quick and dirty solution for adding grip to your treads. My son and I came up with this "solution" earlier today. Go ahead and hack away. I'm sure someone can do something interesting with this idea.
Here's my description from the YouTube page:
Use rubber bands of similar width and length. These #33 size bands were picked up at an office supply store. Cut and lace them through the holes of the tread as shown in the video. Secure them by simply making double or triple knots at the ends of the rubber bands. Make sure the knots are on the inside of the tread. Keep the tension snug, but loose enough so the rubber bands not bind the treads. While far from perfect and not very pretty, they provide a lot more traction than bare tracks/treads while still allowing the vehicle to spin. Have fun and good luck.
Yes - and it is pretty expensive! We were trying to come up with something simple and relatively effective. The Lego produced solution also would appear to result in a very rough ride. The laced rubber band solution fits our needs for a tiny fraction of Lego's product. On another note, has anyone tried using Sugru to modify tracks?