Sputnik is a content management system (CMS) designed for extensibility. It works as a wiki out of the box, but can be extended into other things. It offers editable nodes, history and diff, user accounts with optional email validation, a flexible permission system, RSS feeds, and more. Sputnik supports access control and has editable templates. It can be used to maintain a personal Web site that doesn't look like a wiki and that only you can edit. Sputnik is easy to install on shared hosting without root accounts.
TM++ is an embedded, portable, persistent Topic Maps engine. It is designed to work according to the ISO standards for TMDM 1.0 and XTM 1.0/2.0 on Windows and most POSIX-compliant operating systems like Unix and Linux. It has interfaces for C++, ALLEGROCL, CHICKEN, CLISP, CFFI, C#, Guile, Java, Lua, Modula 3, Mzscheme, Ocaml, Octave, Perl, PHP4, PHP5, Pike, Python, R (aka GNU S), Ruby, Lisp S-Expressions, Tcl, Common Lisp/UFFI, and XML.