4GB Mushkin RAM Memory $63
Sorry, this deal is expired.
Newegg has a Set of Two 2GB RAM Memory Cards (240-Pin SDRAM DDR2 800 PC2 6400) by Mushkin for just $62.99 after this $20 mail-in rebate (through 10/8). You'll have to install these yourself, but it's a great price for four gigabytes. Shipping is free and there is no sales tax (except CA, TN, NJ).