If my math is right...
A $640 USD investment in bitcoins during the month this thread was created (June 2011) would be worth approximately $20,000 USD today if you didn't cash out between then and now.
Then today 2017
Bitcoin jumps above $1,000 for first time in three years
http://www.reuters.com/article/us-global-markets-bitcoin-idUSKBN14M0IF