When backing up your wallet.dat to usb or whatever, I just rename it to whatever coin it is for, eg: Bitcoin.dat, litecoin.dat, shitcoin.dat etc, then if I ever need to use it I know which it is, and then simply rename it back to wallet.dat
Within the first couple of days in December last year on my nvidia gtx 260 , eventually realised I was better off buying in because I was sure they were gonna be worth a million dollars each in a couple of days time if I never Bought in at $12 each with $1500
I think with gpu miners switching to litecoin when asics become mainstream, you would see these miners ''dumping'' litecoin for bitcoin, and bringing the litecoin/bitcoin price 'down'! (until they realise how much faster and more commercial litecoin is, compared to bitcoin) Although bitcoin in my eyes will prevail as a secure store of value, I don't see it as a currency you would buy your bread and milk with at your local store in the future. Get ready for dirt cheap litecoins people!