Rate my Product : QueryCell
tzury: Nice,
However, a question raised in my mind. 
Are you targeting Excel's power users, such as analysts and accountants or software developers?Since "standard" users are not going to learn SQL your market is narrowed to developers only.You may add a GUI based Query-Builder such as can be found in MS Acess and MSSqlServer and other DB systems and by these you can gain more market share.Build an easy to use wizard and let the end user choose between SQL mode and GUI mode.