ThinkPad T61 Model Name: 64665WG Part Number: NI25Wxx ...
4GB 2X2GB Memory RAM for Lenovo ThinkPad T Series T61 ( Type 7665 ) 200pin 667MHz PC2-5300 DDR2 SO-DIMM Black Diamond Memory Module Upgrade System Specific Memory - Newegg.com
2GB RAM Memory for Lenovo ThinkPad T Series T61 (7664RYU) Black Diamond Memory Module DDR2 SO-DIMM 200pin PC2-5300 667MHz Upgrade System Specific Memory - Newegg.ca
OFFTEK 1GB Replacement Memory RAM Upgrade for IBM-Lenovo ThinkPad T61 (6464-xxx) (DDR2-5300) Laptop Memory at Amazon.com
Lenovo T61 Ram for sale | eBay
IBM Lenovo ThinkPad T61 15.4" (2.20GHz Core 2 Duo, 4GB Ram, 320GB HDD) Linux