No, because I prefer to use a separate address for every transaction.  I don't like to re-use addresses (which is required in the case of a tip jar).  If anyone ever feels an overwhelming desire to tip me, they typically PM me and request an address to send the tip to.

If anyone has ever sent me a tip they should never re-use that same address to re-tip me in the future.  It is necessary to get a new tip address every time.  I frequently discard old private keys and addresses after I've used them, so unless you check the blockchain and verify that there are still currently unspent outputs at the address, tips sent to an address that I've used before will likely end up in the great bitbucket in the sky never to be spent by anybody again.