Perhaps you will consider investing in ancient coins. You can read about investing in uncleaned ancient coins as a sound investment on our blog (long URL changed to tinyurl for your convenience): edited
http://www.youtube.com/watch?v=AOfOKDD-rak Check out this you tube video on Spare Change: The Liberty Head Double Eagle Gold Coin by Marc Apsolon. Excellent and interestng information on this great coin, and some good strategies in collecting them.