Best Buy: Lenovo 12" ThinkPad Notebook 2 GB Memory 80 GB Hard Drive Black X61-2.0C2-2-80-X-7P64
CMS 8GB (2X4GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with IBM Lenovo® Thinkpad X61 Notebook Ddr2 Pc6400 Sodimm - A41 at Amazon.com
Lenovo IBM ThinkPad X61s Core 2 Duo T8100 8GB RAM 100GB (7200rpm) HDD Win7 64bit | eBay
2GB Memory RAM Upgrade for the Lenovo Thinkpad R61 Series, T60 Series, T61 Series, X60 Series and X61 Series Laptops (DDR2-667, PC2-5300, SODIMM) at Amazon.com
A-Tech 8GB RAM Compatible for Dell Inspiron 3252 Small Desktop | DDR3/DDR3L 1600MHz SODIMM PC3L-12800 204-Pin Non-ECC Unbuffered Max Memory Upgrade Module at Amazon.com
RAM memory for Lenovo ThinkPad X61
Finally replaced the fan, battery, and wifi in my X61. Only other area of upgrade would be getting an LED kit for the screen. : r/thinkpad