Birthday Ideas?

So my birthday is coming up, and for it going to a restaurant with friends then some of them are coming back to camp in the garden. We are going to be doing an all-nighter and need some ideas on what to do, here's what we have got already:

Silly String Fight
Whipped cream fight
Mini obsticle course (in the dark)
Scrabble,cluedo ect...

Please post some suggestions as comments.