Cannot access my bitcoins because my wallet is still synchronising. What can I do to spend them immediately? I have purchased bitcoins and have downloaded Bitcoin-QT, but my wallet is taking forever to synchronize to the network.

I can't access my wallet because it is still in the sync process. I have the record of me paying for the Bitcoins, the confirmation email, etc., and the address it has been sent to. I desperately want to start spending them. What can I do to gain access immediately without waiting for the synchronization to run its course?
One solution is to export (in your privacy) the private key connected to the address on which you received your Bitcoins (or simply all private keys). This can be done using a command line tool known as pywallet.

Then, you can import this key (or all your keys) into another wallet. Browser-based wallets such as https://blockchain.info/wallet do not require syncing. Hence you can immediately spent your coins. For the bĺockchain.info wallet the procedure is described on their website.