Working on dismantling my Exchange 2010 DAG's right now, and just wanted to share my sads. I built the Exchange infrastructure here about 8 years ago with Exchange 2003 - had no idea what I was doing then. Took an old P3 800 server and beefed it up with some 10k raptor drives and a RAID controller, and it ran great on there for several years before I P2V'd that server into a Virtual Server 2005 R2 machine - my first Dell rack server, a PowerEdge 2950. And then a few years down the road we went to Exchange 2010 and I had to set up a demo of Exchange 2007 to migrate from 2003 to 2010 - that was interesting! And then the Exchange DAG's...wow that was a lot of learning, but eventually had all of our mailboxes replicated to 3 different sites.
Then just a few months back Microsoft released their non-profit pricing for Office 365 - free for E1! Can't beat that, they manage my infrastructure and I keep the fun part, and later on we can upgrade some to E3 for cheap...plus Lync, and SharePoint Online (that'll be a project soon, to move our SharePoint stuff out there!), and possibly even our public website. Fun times, but still sad that the infrastructure I built is going away!