Because the question is sure to come up repeatedly, I'll try to keep this list current as various springs come out... Here are the ones I know about right now and the size of drop they provide:
TRD (link)
Front: 1"
Rear: 1.5"
MSRP: $250
Tanabe DF210 (link)
Front: 1.7"
Rear: 2.1"
MSRP: $230
Tanabe NF210 (link)
Front: 1"
Rear: 1.7"
MSRP: $250
Eibach Pro (link)
Front: 1"
Rear: 1.2"
MSRP: $319
Eibach Sportline (link)
Front: 1.2"
Rear: 2.2"
MSRP: $319
Hotchkis (link)
Front: 1.375"
Rear: 2.25"
MSRP: $242.95
Tein H-Tech (link)
Front: 1.2"
Rear: 2.1"
MSRP: (in development)
Tein S-Tech (link)
Front: 2"
Rear: 2.9"
MSRP: (in development)
H&R Sport (link)
Front: 1.4"
Rear: 1.3"
MSRP: $329
TRD (link)
Front: 1"
Rear: 1.5"
MSRP: $250
Tanabe DF210 (link)
Front: 1.7"
Rear: 2.1"
MSRP: $230
Tanabe NF210 (link)
Front: 1"
Rear: 1.7"
MSRP: $250
Eibach Pro (link)
Front: 1"
Rear: 1.2"
MSRP: $319
Eibach Sportline (link)
Front: 1.2"
Rear: 2.2"
MSRP: $319
Hotchkis (link)
Front: 1.375"
Rear: 2.25"
MSRP: $242.95
Tein H-Tech (link)
Front: 1.2"
Rear: 2.1"
MSRP: (in development)
Tein S-Tech (link)
Front: 2"
Rear: 2.9"
MSRP: (in development)
H&R Sport (link)
Front: 1.4"
Rear: 1.3"
MSRP: $329