An open source project to collect and distribute "Tasks" for MSBuild. lats of them available already like FTP, Source Control, Windows Script, Zip and more.
SourceCode and Compiled Binaries for two low-level system information tools: NtSysInfo explores Windows internals and enumerates system processes, windows, threads, objects. The WhoUses utility allows you to determine what process has a file or DLL locked.
GPPG is a generator for parsers which takes input like YACC/BISON and outputs thread-safe C# parsers... uses a FreeBSD-style license, and there is an accompanying scanner (GPLEX)
xacc is an opensource multi-language IDE written in C# ... it handles syntax highlighting etc for everything from Boo and C# to Ruby and Perl, to Caml, F#, Scheme and Lua, and even Yacc, Bison, Lex and Flex ... and PowerShell.
It has project support for C#/C++, Nemerle and Boo, and Yacc/Flex, NSIS, etc.
A job scheduler like quartz.net (or like Java Quartz) to offer enhanced scheduled-tasks (or cron) -like functionality to .Net applications at the thread/process level.