This could help on client sites where they've not changed the out of the box default assemblyinfo settings, and you want to know when a build was made of a particular assembly
http://www.geekproject.com/showtopic.aspx?ID=21
When you specify that you want to have Buildnumber and revision automatically generated then the compiler (C#) will generate Buildnumber as the number of days from the 1st of January 2000. The Revision is generated as the number of seconds from midnight divided by two, but it will NOT take daylight savings time into account.
Remember the setting in AssemblyInfo.cs is...
<Major><Minor><Build><Revision>