Meritline offers this Screen Protector for Apple iPhone 4 3-Pack for $1.29 with free shipping. That's $0.43/protector and among the best prices we've seen for this collection of screen protectors. (We saw this same 3-pack for 30 cents less in February; it's a current low by about a buck.) These screen protectors feature scratch, dust, and UV protection.

Expect this item to take two to three weeks to arrive.