Had this question today from my good friend Cedric. He needed a way to display non-SharePoint SQL data on a SharePoint site. Well, looking around on the net I found these options:
A. You can off course use the built-in Business Data catalog for this, which may be a little bit of overkill if all you want to do is display a simple table.
B. You can buy a SQL Data Viewer Web Part:
Bamboo solutions has one: http://store.bamboosolutions.com/pc-71-1-data-viewer-web-part.aspx (500$ / server licence)
Lightning Tools has one: http://www.lightningtools.com/pages/lt%20data%20viewer%20web%20part.aspx (400$ / web frontend server)
C. You can or develop you own data viewer web part using this post:
D. You can use the Data View Web part in SharePoint Designer:
This web part is configured with SharePoint Designer. It can use a wide range of data sources including XML files, web services, SQL and Oracle databases and SharePoint list/library content. The rendering is XSLT driven with SharePoint Designer providing a drag-and-drop interface to generate the XSL.