lanyard (wrist strap) for iPhone 4

I've been using a Nexus gel type bumper with my iPhone 4 for several months now but when I took it off this week I noticed that the stainless steel surround has abrasion marks on it a bit like lots of highlights, I attribute this to particles getting under the skin and then movement of the cover causing abrasion damage.

I'm now looking to replace it with a very simple wrist strap as I use it on site in my work and don't want to drop it. I was given a Voi Interim case for Christmas which indeed does have a wrist strap but the fit isn't too good and I've also gone off the idea of any type of bumper now.

Does anyone know of a good wriststrap product? On a related note I see that the Google Nexus whilst not quite as elegant as the iPhone doesn't need a protective case. I really hope that the iPhone 5 will be a more practical design (please Steve Wozniak!)