I have added a page with code documentation of TYPO3, generated with doxygen. It provides a nice overview of the latest code from trunk and allows to search for classes, functions and properties in the bleeding edge TYPO3 core.
Doxygen scans the source code of your project and generates well structured overview of it. It extracts code comments, method signatures and method/class dependencies and merges them to form easy-to-read items:
After searching a while for an existing version of TYPO3 trunk without success, I decided to generate my own. You can find the TYPO3 core API of trunk on a seperate page of this website.
The search form allows you to find any function in the TYPO3 core within a few seconds and get all facts of its use, parameters and dependencies to other classes/functions. It gets updates on a regular basis via cron. If you like it, you can use it: