Gmail makes a pretty good “other inbox”. Every Gmail account supports “plus addressing”, which means you can create unique email addresses for your Gmail account by adding “+blah” to the end of your email address. For example, if my email address was jbaer1975@gmail.com, I could give Amazon jbaer1975+amazon@gmail.com and give Facebook jbaer1975+facebook@gmail.com.
This helps with spam, because if you want to know why you are receiving an individual message you can “Show Details” to see the To address that the message was sent to. Then if you want to stop that sender, you can create a filter to delete them automatically. For now we’ll just ignore the fact that many websites won’t allow you to sign up with a “+” in your email address. In fact, even Google Alerts won’t let you use a plus when you sign up!

Unfortunately, you won’t notice most of the interesting things you would see with OtherInbox because messages aren’t automatically grouped by the address that they come to. And you still need to look at messages one at a time or do custom searches to group them.
Even if I give out different email addresses, I still end up with this unmanageable list:

Giving out different email addresses to every website is a great foundation for OtherInbox, but there is a lot more to it. OtherInbox displays messages in a unique way that allows you to jump right to the messages you want to read now and ignore the ones that you want to read later. You don’t need to scan through them one-by-one. Without any effort, you instantly know if someone is spamming you and it can be blocked with a single click, rather than having to configure a filter or rule.
Once you give out a bunch of different email addresses with the plus in them, its still a pain in the butt anytime that you want to reply. If you just reply normally, you will expose your real email address. In order to reply and have it come From the correct email address, you need to go through a tedious process of verifying the email address by sending a message to yourself, clicking the link, and then selecting the proper address when you reply. With OtherInbox, this all happens automatically and it always replies from the correct address without you having to set anything up.

So yes, you can use Gmail as your “other inbox”. But chances are, you will still get email overload and that mailbox will still become a big pile of junk. You still need to look through your messages one at a time and don’t have an intelligent way to batch the messages into actionable groups. You might create filters to stop some of the spam, but you probably won’t notice many of the ways your email address gets shared, sold and abused. Anytime you want to reply, you need to go through the verification process and send yourself an email to set up the correct From address.
There is a lot more to OtherInbox than just giving out different email addresses. It’s a great foundation, but it’s just the start. Give OtherInbox a try to see how it can cure your email overload!