Fortunately, there's a URL you can bookmark which will jump straight to a specific account's Inbox. This one leads to my default account:
In contrast, this one leads to my work account:
You'll notice the only difference is a single, magical number. I had a personal Gmail account before starting my job, hence the lower number.
If you simply navigate to a particular Inbox in your browser, you should be able to bookmark that little sumbitch right there. But if you're a longtime Gmail user with existing bookmarks, you were probably too busy punching the drywall in frustration.
I hope this tip prevents you from goin' all stabby on something.
This tip also works with Google Calendar.