Sens'it 3 - Six sensors, a button so many possibilities
Open DBDiff - A database comparison tool for Microsoft SQL Server 2005+ that reports schema differences and...
FriendlyData - Communicate with databases like a human
a7 SqlTools - Tools for MS Sql management with search, explore and comparison functionality.
mlsql - Infer SQL queries from plain-text questions and table headers.
DBComparer - Free Compare database tool - DBComparer 3.0 is a professional compare database tool for comparing Microsoft SQL Server 2008 (and 2005) database structure.