I've been thinking about phones a lot lately - payphones in particular.
Warning: link to novel-length rambling follows - like to the point I'm giving little section names, a title and everything, and had to toss it into a pastebin thing (but not pastebin, it looks like they didn't like my use of the word fuck or something) rather than this comment like I intended.
Basically, it's an invitation to waste some time. It can be summed up by "Idk, I'd make a weird voicemail or PBX system and leave the number at remaining payphones, I guess. That could be fun."