Ideas For My Partners 21st!

It's my partners 21st in a couple weeks and i want to give him something unforgettable!

I have themed it as '21 things for your 21st'....

i have a few ideas but am a lil stuck!! I would love to get him some unbelievable experiences eg- v8 hot laps, etc etc but i dont want it to cost a small fortune!! Any ideas??