Very clever idea. I did some more searching on Amazon and found a wide variety of products, including the one mentioned above - different sizes, some for just a one cup at a time, others larger, like your instructable for a "2 cup" size of coffee.



http://www.amazon.com/MiniMinit-filters-holder-one-coffee/dp/B001T3WJ4M/ref=sr_1_cc_2?s=aps&ie=UTF8&qid=1328811433&sr=1-2-catcorr



I used search strings like "refillable coffee filter bag" "empty coffee bags" "empty tea bags"



For those in UK I also found on Amazon.co.uk

http://www.amazon.co.uk/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=tea+bags&x=0&y=0#/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=empty+tea+bags&rh=i%3Aaps%2Ck%3Aempty+tea+bags



so looks like there are plenty of options and prices!! Most excellent idea as my coffee maker just died and the last one I got for "free" by buying a few months worth of coffee from Gevalia.com - but they no longer offer the free coffeemakers for new subscriptions...and I'm too stingy to want to shell out $100+ for the K-style coffee makers (although I am enthralled with the single shot coffee maker concepts because I don't drink 8 cups of coffee in a day - I would make the 8 cups in my old coffeemaker thermos carafe and then reheat the next day or two when I wanted more. Of course, reheated is icky (but better than nothing... or maybe not?)... I already have gobs of loose coffee so I know I can get the reusable k-style filters if I do finally find a K-style machine at a reasonable price. But this will get me going in the meantime!! Thanks so much!