The program supports tabbed browsing--nothing new at this point--but does add the very nice ability to collect tabs into groups and then load an entire group at once. For example, I put PC World, MacWorld, and Slashdot into a group I called 'ComputerNews'. I can then load all three by a single menu selection. This feature is very useful for research, as you can summon a set of related sites as needed, without manually opening each one. (Firefox allows you to open all the bookmarks in a folder, but not to have logical groupings which are not related to folders.)
The browser also supports 'mouse gestures', which let you navigate without clicking buttons or typing keys. Hold the right mouse button down, sweep right to left, and you go back; left to right, and you go forward. The gestures take some learning, but in time, they would likely become second nature.
Also included are many content filtering features. The program comes pre-configured to block many types of ads and popups.
Unfortunately, Crazy Browser is very much a small-team project. The interface is functional, but ugly, and quirky in places. To close a tab, you must go to the upper-right corner and click a close box there, instead of there being a close box on the tab itself. The toolbars use generic icons. It auto-imported my Explorer bookmarks, but didn't ask about Opera or Firefox. Development on the program seems to have stopped; the last beta was in February 2006.