The rims are now extremely expensive and rare, having been discontinued. This type of rim is especially popular in Houston.
The term fo' fo's was popularized in the song Still Tippin by Mike Jones Feat. Slim Thug and Paul Wall. Tippin means to cruise from side to side in your car, so if you're tippin on fo' fo's, you're cruising around on your really expensive, rare wire rims.
Unassuming Business Man: *Grabs wannabe thug, knees him in the stomach, hurls him to the pavement, then curbs his ass, takes his cash, and poops on his chest*