In my SQLBulkCopy article, I mentioned that you can quickly copy data from anything that implements IDataReader to a SQL Server table using SQLBulkCopy (new in .NET 2.0).  In this SQLTeam forum post, Jesse Hersch (jezemine) tells us that SQLBulkCopy only actually uses 3 methods of the interface.  This means that it is very easy to quickly create your own custom class which implements this interface to bulk copy pretty much any type of object collection or array to a SQL Server table.  He even provides code for a simple abstract SqlBulkCopyReader class that you can inherit from to implement only the necessary parts of the interface.

So, if you need to persist large amounts of data from your .net applications directly to SQL Server, and that data is not stored in DataTables, be sure to consider this option.  Thanks, Jesse !