An excellent, inexpensive store if you need hair-related objects. Anyone can buy, although stylists are eligible for a "Sally card" (kind of like the discount cards required by some fascistic supermarkets). They carry everything from electric clippers to curling irons, styling gel to depilatory gel, permanent to spray-in dye.
The staff are helpful and open-minded; due to my lack of foresight, they saw me during each stage of my quest for blue hair. Each salesperson seems to have their own area of expertise; if the person you need isn't in on a given day, they'll tell you when to return.
Although they don't carry Special Effects, the premier unnatural hair dye, their store brand, Beyond the Zone, is rather good; I've had colorful results with "Midnight Blue." Their bleach is much cheaper than a bleach kit from Wal-Mart or Hot Topic, and their selection much larger.
Most locations are open 7 days a week, closing at about 7 p.m. Monday-Saturday.