Happy to share my system. This isn't supposed to be a jab at zero inboxing, I just never felt the need to physically move email. I've been using multiple addresses, filters and tags since long before I actually had things to do and they actually continue to do the job pretty well.

My current set-up looks something like this:

• Bulk inbox for everything unsorted.
• Business inbox for everything sent to me about my job by a person.
• Ad inbox for everything sent to me about my job by a robot.
• Accounts inbox for bills I intend to keep and any financial mail.
• Chat inbox for forum updates and responses to blog posts. >90% university-related discussions.
• Private inbox for close friends and family. When my phone is not on priority mode, I also get a notification for these.
• Subscription inbox for newsletters and advertisements at me personally. I go through these after work and sometimes tag stuff I want to read during dead time (e.g. waiting in line).

Bulk, Ads, Accounts and Subscription get automatically marked as read when I shut down the program.

Filters sort >90% of my mail for me and are mostly based on the address used, as it saves me the time to manually add the sender to my filters (and hope they only use one email). Since my starting screen shows the bulk folder, I can just glance at the other <10% and move on, as it's usually unimportant. Today's bulk mail includes two Japanese book shop coupons, Reddit, two seminar invites, a reminder at myself and a meetup proposal.

I also have an emergency email which has no inbox but forwards mails directly to my phone in all situations. Never been used, of course, because nobody remembers obscure email addresses in emergencies (and my life actually isn't as action-filled as one would expect the life of a business consultant with a dozen email filters to be...). Still, I like the idea of handing them out in the hope that it makes my other addresses "non-emergency" by contrast.

Each inbox currently holds several thousands of emails and after a few tantrums at having deleted that one email, they will likely stay undisturbed for the next couple of years.