Tools for SQL Server

Object Comparison:
AdeptSQL Diff
AlfaAlfa Software - SQL Server Comparison Tool
ApexSQL – SQL Diff
Best SoftTool – SQL DBCompare
e-Dule - DB SynchroComp
PrimeLogics - DataVision 2007
Quest – SchemaCompare
RAC4SQL's QALite (Free)
Red Gate – SQL Compare
SQL Effects Clarity
TASC - SQL Delta
Teratrax Database Compare
TulsaSoft - SQL Examiner
Voltex Data Systems - SQLDBcontrol
XpressApps - sqlXpress Diff
xSQL Software - xSQL Object


Data Comparison
ApexSQL – SQL Diff
Best SoftTool – SQL DBCompare
Quest - DataCompare
Red Gate – Data Compare
TASC - SQL Delta
TulsaSoft - SQL Data Examiner
xSQL Software - xSQL DataCompare

DTS Comparison
Red Gate – DTS Package Compare

Server Comparison
Quest - ServerCompare

Free Tools
RAC4SQL's QALite (Free)
SQL Effects Clarity CE Edition

courtesy to Arnie -- thanks Arnie