We have created many versions with different rule sets. The latest incarnation is called 'Hide and Seek Lottery Balltag'. I came up with this as an attempt to add more strategy than the usual "get the slowest kids" formula. Normally the amount of hiding in Hide and Seek Balltag is based on who is it. If a slow kid is it, nobody is hiding. Everyone is out calling positions "Hes over by the mailbox chasing so and so!" For this version, I made small cards (cut paper) each with a number ranging from 0-9. Each player gets 2 cards at random. The goal is to have both your cards total 4 or less.
The rules: Don't tell other players what your numbers are. When you get tagged, the person who hit you gets to trade their highest number card for one of your cards. You can hold your cards face down and they have chose one without knowing what they are. So they may end up with a worse card. No tag backs. hehe. Then I did an example tagging to make sure everyone understood. "Thats it! Now run!"
15 minutes into the game there were already a ton of card exchanges and players screaming in agony while others jumped for joy at their new cards. A few minutes later I saw my daughter Sasha standing under the car port. I ran over and whispered "Thats a terrible hiding spot! You better get out of there!" Then she broke it all down for me. "Im hiding here on purpose because I have bad cards. The players who are in the best hiding spots have the best cards. The players with the worst cards are trying to get tagged to get rid of them. Some players are purposely getting tagged to figure out what cards everyone has." Some of these kids were actually counting cards and figuring out which cards were traded based on expressions during exchanges. They turned ball tag into a card counting gambling fiasco. Kids are just to smart for their own good these days. :)