Abbott Racing - SAAB tuning and performance house based in the UK
Automotion Motorsport - official North American distributor for SQR engine management software for Trionic powered SAABs.
BSR - Professional car tuning and performance technology
ECU Project - online forum on ECU tuning
Eric SAAB site - a SAAB owner's site that has a few good DIY write ups.
Forge Motorsport - makers and distributors of all kinds of performance parts, they are most noted for the Forge diverter valves that replace the stock Bosch unit on SAABs
Genuine SAAB - aka Taliaferro Imports, a small shop that specializes in SAAB parts, tuning and maintenance. Home of the 11-second SAAB drag racing car
Hyperboost diverter valves - made to replace the stock Bosch valves, but have better operation. Very similar to the Forge diverter valves.
Jak Stoll Performance - SAAB tuner based in Oregon.
JZW Tuning - SAAB ECU tuner based in Colorado, does Trionic 5, 7 and 8.
Map Tun Performance - specializing in SAAB software development, Map Tun is a Sweden based tuner.
MP Performance - tuner that offers a few parts for SAABs
SAAB-Tuners - Dutch SAAB tuning site with some good information
Smart Performance - makers of the SAAB Manual Boost Controller and Anticipator (MBC-A), a cheap way to manually control the boost on SAAB's vehicles, allowing you to get more boost out of your turbo than the factory ECU will allow.
Swedish Dynamics, aka SAAB Performance Parts - a supplier of many performance parts for SAABs.
Trionic suites - professional tuning software for Trionic ECUs
TrollTuner - Taliaferro's SAAB tuning blog
900 Aero Site - specializes on the classic 900, lots of information here, check out the "Tech" and "DIY" parts.