Coming from C++, if you do not want to become crazy using untyped languages you might be interested by the haxe programming language.
A nice inference typed language which can be compiled down to neko bytecode (much like java bytecode), JavaScript (for the client side), Flash movies (idem), and even C++
Plus, haxe has a mod_neko for apache and lot of libraries to manipulate databases and templates.
Just create a web application which will answer your question.
Some place where people will come and complain about something they miss. And where needs will be merged and shaped and will finally lead to "the next killer application for a niche".
If it works you will have plenty of fresh ideas for the next time you will have the time ;)
A nice inference typed language which can be compiled down to neko bytecode (much like java bytecode), JavaScript (for the client side), Flash movies (idem), and even C++
Plus, haxe has a mod_neko for apache and lot of libraries to manipulate databases and templates.
http://www.haxe.org