I just give NXT as an example.
1. dowload supernet lite client, open it and click next, next to finish account creation process.
2. Go to http://www.nxtinfo.org/nxt-faucet/ to claim a few NXT to activate it. You could input fake email.
3. Create BTC address, Send btc there
4. Open NXT Asset Exchange, sell the BTC (superBTC)for NXT
Duplicate the upper process
5. send every account's NXT to one single NXT account, sell out for BTC, withdraw to you address.
Another way is to deposit to exchange or gambling site and withdraw!
How much is the transaction fee while converting to alts? That could be a dampener!
Gambling sites sometimes ask you for the reason for withdrawal, if you deposit and withdraw without making any bets. You should be careful about that.