Supposedly iPhone 4 reception issues are fixed if you just hold the device differently (uncomfortable and awkward!) or put it in a Bumper case (ugly!). This StealthArmor for the iPhone 4 might be the first attractive pseudo-solution.
StealthArmor appears to be more of a self-adhesive covering than a case, but it's supposed to keep your iPhone 4 free of scratches just the same. As it comes with side panels that prevent your fingers from coming into direct contact with the device's antennas—which is supposedly what causes the reception issues—it might also prevent your signal from dropping:
It's not a real solution, in my opinion, as I don't think I should have to put my beautiful gadget into any sort of case to prevent my signal from disappearing, but at least it's decent looking and seems to work.
The StealthArmor is priced at $25 for the clear version or $45 for one of the fancier patterned versions. [StealthArmor]
Update: Vincent from Slashgear says not so fast, this thing doesn't seem to work:
UPDATE 1: We got to work early this evening to test Fusion of Idea's claim but it's still inconclusive. A quick test of holding iPhone 4 with our left hand DOES NOT yield a better reception with the applied material, as you can see for your self from the pictures below. This is a pretty BOLD claim by Fusion Of Ideas. -Vincent