Testing Multiple Login Sessions Simultaneously

One annoyance in developing websites is that you sometimes have to log in and out all the time to test interaction between multiple users.

Have you ever visited or administered a website (say, www.example.com) which lets you visit "www.example.com" or "www2.example.com", etc, and doesn't forward to "example.com"? Did you ever try logging in at one subdomain, and then switch to another? You'll be logged out, it's a different login session. If you needed to test something remotely with multiple users logging in at once, that's a nice trick to use.

Now let's do the same thing locally (*nix systems only afaik, sorry):

In /etc/hosts you should see:

127.0.0.1 localhost

Add the following:

127.0.0.1 localhost2
127.0.0.1 localhost3
127.0.0.1 localhost4

And so on for however many you need. Now each one will access your site with a different session, so you can log in as a different user for each.