Malpaso,

I had a Rite-in-the-Rain pen. It did not work near a well as the Space Pen. I took some Rite-in-the-Rain paper and put it in the bathroom sink. I turned on the water and put the paper under the water flow. I then tried different pens to see how it would work. Only the Space Pen would write on the paper and not smear. The Rite-in-the-Rain pen did not write clearly with the water running. This seems like a worse case situation of being in the rain and needing to write a note.

Gaffers tape and orange marking tape also work well for leaving messages. The marking tape is the hardest to write on because it does not have its own hard surface to write on.