Happy 21st birthday Lotus Notes. The best ever email, collaboration, IM, workflow application (all bundled in one) has completed 2 decades. No matter what Microsoft tries to rubbish the product, the truth is that Lotus Notes rules.
Its the only product that doesnt need a rip and replace every time a new version hits the market and is an application that supports true backward compatibility.
I run a Lotus Domino 8.5 test server on my 5 years old Windows XP PC with 1.5 GB RAM along with the rest of the applications. And still my system doesn’t complain. If it was Microsoft Exchange 2010, heck i cant even install it as my hardware / Operating System is not 64 bit. I rest my case.
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Alternate Investments 
Very true! We have a number of small business customers which want to upgrade to Exchange 2007 and they are forced to buy a new Server and a new OS to run 64 bit OS.