Question: I'm on Windows. 

A couple years ago when I switched from Outlook to Gmail (Google Apps), Google provided this awesome little standalone gmail client that was just a single-purpose Chrome install. It launched like a normal application, stayed updated when I updated Chrome. It was Chrome in a separate application that launched only gmail, stayed logged in really well, and "felt" like a gmail mail client, with the gmail interface. It had it's own little red envelope icon, it was a windows app. (I remember there was no Mac equivalent.)

I found it while looking through the "this is how you get your company to switch to gmail" documentation that Google provided. 

I just repaved my box and now I'm looking for this thing again, and I had no idea it would be impossible to find. I've spent literally 2 hours looking, searching, googling, etc. I'm losing my mind. 

Anyone know how I can get my hands on this? I used it all day every day for 2 years, so I know it exists :), but I can not find it. Any assistance would be gratefully received.

Answer: 
You can use an application shortcut in Chrome. This essentially tells Chrome to create a shortcut which will launch a browser window which will show the requested webpage. It will only show the window, no address bar, bookmarks, etc. They also have their own icon in the start bar, so they appear as a separate application.

To make an application shortcut, go to the website you want (in this case Gmail). Then click on the wrench (options menu)->Tools->Create Application Shortcut.
It's a link in the cpanel of your google apps domain. Look for "advanced tools" then scroll down to "Google Apps desktop features". There should be a download link there.