You've got snail mail, voicemail, email, and maybe even gmail. Now, Japanese toy maker Takara introduces Ma-Mail.
Basically, the idea is that you give someone a can filled with soil; they water it, and in 5 days, a bean plant sprouts up with one of six short messages printed on it. You can see the TV commercial here in Windows Media format.
(Preemptive note to language wonks: Yes, I know that the last syllable in 豆 is shorter than the long sound that starts メール. Cut me some slack.)