We use the LSX Toolkit to easily provide an Active Directory object browser for our product - FirM. In fact, we've open-sourced the project, and you can download it from here. You see, the LSX - The LotusScript eXtention Toolkit - allows you to put C++ code into a library package (a DLL in windows, a library in Unix/Linux, etc), and then have that extend LotusScript. Very very powerful. You can use it to do specialised Notes stuff - Bob Balaban for instance, had a 'Script Expander' Package which made every single C-API call available to LotusScript (you cant do them all using LotusScript to C-API techniques - as we demonstrate here in this other open-source database)
Why mention this ? Well the only publically available version of the LSX toolkiit (available here) is over eight years old. The old one wouldnt compile in Visual Studio 2005 or VS 2008, making it nigh on impossible to use dot-net v3 or v3.5 exensions in your LSX.
A very very good use of the LSX toolkit is shown over at the Genii Software site - Midas. Some pretty amazing stuff can be done with LSX.
A new version was promised at the 'Beat the Developer' session at Lotusphere about two months ago, and we've still not seen hide nor hair of that. Yet. I still have hope. I understand how busy everyone is in Lotus Dev, and in no way wish to tell Mr Peters how to do his job. Some public announcement around this would be cool.
One hates to keep asking the same question all the time, but as Roosevelt said: "If I have to choose between righteousness and peace, I choose righteousness"