I came across both of these items a while ago, but keep forgetting about them when i need to use them. The first is the COLLATE statement in T-SQL. Sometime different databases have different collations and when you try to query between them a collation error occurs. Now i used to always use one of the collations, ie collate Latin1_General_CS_AS. But i knew there was a default one, and i finally found it again (COLLATE database_default).
The other function Coalesce is a C# 2.0 item that does a thing similar to T-SQL's isnull()'s function. So:
string x = null;
string y = null;
string z = "123";
string value = x ?? y ?? z;
(value == "123") == true
So instead of using the :? statement checking nulls, it makes it alot cleaner.