There was a recent Wall Street Journal article about Friends & Family (F&F) discount coupons. Traditionally, retailers have sent discount cards to specially selected clients via snail mail, but the trend has moved to email versions for online purchases. The problem is that these "exclusive" discount codes have propagated like wildfire, benefiting individuals whom these retailers would consider neither friends nor family.
If you are in search of these discount codes, check out this coupon aggregation site. It's extensive, but by no means complete. For example, it doesn't show Red Envelope discount codes that I found elsewhere.