I have now had the PO Box address through for you to send things for the card for Felipe Massa, however it will not be active until Monday 17th August 2009. Edit 14/8/09: You should be alright to start sending things through now - it will take a couple of days with the weekend, even if you're close to here!
The address is:
PO Box 3254
Obviously please put something in the name place - either my screenname, real name (if you know it) or something like 'Felipe Massa get well card'. I would say be creative, but bear in mind that the people at Royal Mail will see it, and will laugh if it's funny. Please don't put anything rude or offensive in the name place though!
If you'd like to contribute to the Get Well card for Felipe Massa, please do. Remember, all it's going to cost you is the price of a stamp. If there are any problems, please leave a comment and I'll get back to you :)
Now, go out and spread the word!