As I typed in the OP, the Grolsch beer bottle washer idea is intriguing (I also picked it up from Justin). Shortly after the OP, the beer bottles appeared in my fuzzy memory. Almost 20 years ago My Lady and I were at a party where some of my buds were drinking something other than Bud. My Lady was enthralled with the bottles with the special tops and asked if she could have them.

So on a hunch I went looking for such bottles where we keep such knick knacks. Sure enough, there they were; one Grolsch bottle and one Salado Creek bottle (a beer from my former home of San Antonio and site of the above party). The washers are a little dry after the two decades but still pliable. Most importantly, they fit nicely on my acoustic and electric with the straps I use on each. Nice enough that I'll break training and have some Grolsch for my regular Friday-night binge instead of my beloved Yukon Jack and thereby get some new washers.

I'll don't mind a little personal sacrifice to protect my guitars a little. ;)

Thanks for the suggestions, guys. For the now the washers win out -- I told you I liked cheap and easy. :D