Griot's has them for ~$2 each (5 for 9.99) as non-woven Micro Fiber Wipe-Down Towels. A quick Google comes up with a company called Clean Tools manufacturing a similarly dimensioned, also non-woven microfiber towel called "Softoss" at a list price of 8 wipes for $7.99 (they're available for as low as 3.97/8 from other retailers which makes them really disposable).

Anyone tried either?

 

I have a set of the Griot's micro fiber towels and like them a lot. I don't remember their official name. However, I just found that Costco has packages of 24 microfiber towels for $10 each. I bought two stacks. So far, they seem as good as the Griot's and a lot cheaper.