Per Matthew Cornell's Inboxes of Our Lives post, I decided it was time for an inbox census.

1. Mailbox - this is outside and gets dumped into the next one before anything else is done with the contents
2. Landing strip inbox - This is a letter tray. I throw in mailbox stuff and anything I find around the dining room that needs to be put away. This is emptied primarily into the inboxes in the office downstairs. Sort of a transitory inbox, like the mailbox.
3. Shower slate - Yes, I have an inbox in the shower. It's a plastic slate designed for use by scuba divers. Great for those ideas that always seem to hit you in the shower, far from most paper, pens, or electronic note-taking devices.
4. My side of the dresser - We have a long, waist-high dresser in the bedroom. Typically my receipts and so on get dumped there. Now and then these go in the landing strip inbox and are processed from there. This needs revision so that there's a proper inbox, plus probably a tray for the things that live in my pockets. This is also mainly a holding location.
5. Desk inbox - This is one of the main inboxes, where all of the stuff from upstairs and that I generate at my desk ends up before it's processed. Pretty conventional GTD.
6. Computer desktop inbox - I have a folder on the Desktop on each of my computers called Inbox, which is symlinked to my home directory as well (mv foo ~/Inbox/ is handy). I've tried putting these on Dropbox so that I only have one inbox across all of my computers, but some of the files end up being pretty large, which clogs the Dropbox sync. So I don't do that anymore. Important: any program that has an optional default download location, I set to dump files in this directory, not on the desktop or a 'Downloads' folder, which is totally a one-trick pony.
7. Other computer inboxes - I have a number of shell accounts on clusters, my web server, and so on. Each of these has an Inbox, but it's typically used only locally. For example, if I need to send some files to our cluster, I usually scp them to machine:~/Inbox/. Then I know where to find new files on each machine.
8. Jott - I normally check Jott using Jott Express, on my computer. I've started using Jott Express to add new items as well, rather than writing them on pieces of paper and putting them in the paper inbox. The nice things about this are (1) I can add to it via SMS, (2) I can add to it via a voice call, which is transcribed, and (3) it's the same on all of my computers, as it's hosted on Jott's servers.
9. Work bench - Okay, this one is really sad to look at. Whenever anything needs filing away in the storage room, I throw it on the workbench. This makes the workbench useless for actual work. I need a big box on the workbench, or to put stuff away directly. I do like batching the storage room stuff, so I think I may go the big box route.
10. Meditation notebook - If you've ever tried mindfulness meditation or the like, you've surely experienced the flood of things bouncing around in your head that you didn't even know were there before. Meditation can be like going through David Allen's trigger list, only better. A lot of teachers will advise you to just let the thoughts pass. That's anathema to a GTD fanatic like me. Why let them continue to bounce around in your head (or -- eek -- disappear)? They need to be out! On paper or something! So I keep a notebook and pen nearby when meditating. When something important pops up, I write it down and go back to meditating. The thoughts don't bother me any more, and I know that they'll get into the system. I typically empty this one right after sitting.

I think that's it. Clearly there are some inboxes that could use tweaking. I didn't explicitly realize before that I had 'feeder' or 'holding' inboxes and 'real' inboxes, but there it is. Most of them arose because I find I'll inbox (did I just verb that?) things more readily if there's an inbox handy, rather than having to go downstairs or whatever. How many inboxes do you have? Any strange or otherwise interesting ones? How many are feeders?