Note: I realize that this is kind of random, but I was making some envelopes for a special letter that I wanted to send and realized that I didn't know how to seal it without being torn to shreds when my friend opened it. I found this recipe at the Allene's craft site. Very easy!
Lickable Envelope Glue
2 parts tacky glue
1 part vinegar
How to use:
Use brush to apply to paper stroking one way.
When that is dry - apply another thin coat stroking the opposite way.
When ready to use, insert letter, moisten, seal, send.