I promised myself that, when I bought a box of Swiffer WetJet refills at the wholesale club, it would be the last box I bought. Something had to be done. Now, to be honest, part of the reason was to help the environment, but the other part was because I was tired of running out of those darn things.
I took some towels, folded them in half cut them into 5" widths. (The towel was just about 25" or so from side to side when flat.) Then I cut two 5" pieces of elastic and serged it all together. Two layers of toweling and two elastic strips. That's it. (The finished piece was approximately 4.75" x 12.")
Within minutes I had a stack of eight.