Nice collection of code that shows off just what the SPS Object Model can do.
Here are some of the tools listed (with source code)
SharePoint Portal Server Content Source Add tool
An example of how to add Content Sources programmatically in SharePoint Portal Server 2003
SharePoint Portal Server Indexer Property Sequence Number Checker
This tool will check the PropSeqNum values for indexes on the index server, and compare the values on all related Search Servers
Document Library file extractor
Extract files recursively from a document library out to the local file system
SharePoint Web Pruning tool
Removes all necessary subwebs recursively for a web at any level in the site collection, without the need to do this manually.
SiteBuilder test tool
Create a series of Site Collections and nested webs for testing purposes
SharePoint User Util
User Maintenance tool for Windows SharePoint Services and SharePoint Portal Server
List Refresh Tool
Rebuilds a list for you in case you need to apply the latest template changes on the list.