DESCRIPTION: Allen is not good with technology he's not used to, so he's more likely than not to miss your call. But he'll get back to you eventually. Possibly.
LOCATION: Basket by the door
DESCRIPTION: Allen checks his hobo mail every morning, and he rises with the sun. If you're feeling lazy and want bootprints on your letter, you can slip it under the door. Papyrus will probably be irritated by the mess, though.