The PC Technology Guide
Outlines the components of the PC's memory architecture and the various memory types and packaging.
http://www.pctechguide.com/14Memory.htm

Viking Components, Inc.
Designer, manufacturer and distributor of computer system memory boards, flash memory and readers, and modems.
http://www.vikingcomponents.com/

MemoKit
MemoKit - Computer memory manager and optimizer, virtual memory and cache optimizer, performance booster. Recover and defrag your ram! Try MemoKit before you upgrade your PC memory!
http://www.memokit4all.com/

Memory-Up
Memory-UP.com: High Performance SD, DDR, DDR2, MicroDimm, Compact Flash, Secure Digital, Memory Stick, Multi Media Card, TransFlash, and xD Picture Card Memory for Notebooks, Laptops, Servers, Digital Camera, Cellular Phone, PDA, and SONY PSP.
http://www.memory-up.com

Memory Zipper Plus
Memory optimization and management utility. Free the memory that Windows neglects and fails to release, defragment the computer's RAM, and repair memory leaks to avoid crashes.
http://www.systweak.com/memzip/

Certified Components Group, Inc.
Certified Components Group is a leading distributor of board level electronic components, semiconductors, discretes and interconnect products.
http://www.certifiedcomponents.com/

Sue Becker
Computational neuroscience, neural network models of perceptual and cognitive processes including cortical and hippocampal memory systems, spatial memory, semantic memory organization, frontal executive control of memory.
http://www.science.mcmaster.ca/Psychology/sb.html

SND Electronics
Distributor of electronic components and computer products including semiconductors, passive components, disk drives, and memory modules. Facilities in multiple countries and US states. Site lists company product lines and manufacturers.
http://www.snd.com

GoldMemory
GoldMemory - Thorough memory tester for CPU & chipset, SDRAM & DDR DIMM, RDRAM RIMM
http://www.goldmemory.cz/

Ramseeker
Ramseeker offers FREE memory and RAM price comparison from all reputable online vendors. Established in 1997, we're happy to celebrate our 10th year saving you money on your next computer ram buy. , SDRAM, DDR, all, at cheap prices. Don't over pay on your next computer ram purchase
http://www.macseek.com