This plugin looks great... though for 'offsetTop' I'd like to have the header fixed in place to a containing div, not a integer (pixels) from the top of the window but specifying a jquery selector (for the containing div). Is this possible?
I do know that datatables does have the 'scrollY' option: this will work if you specify a height in pixels for the 'view port' of the scrolling area. I don't want to specify a fixed height, I just want the header to be always visible when the user scrolls in a given div. To me this seems a lot more useful than either the 'offsetTop' of FixedHeader or the 'scrollY' of datatables options.
A leading competitor, 'Tablesorter', has a plugin that does this (I found it not to work with IE8, but thankfully I don't have to deal with IE8 anymore) - you can specify a jquery selector - although I can't remember if I've acutually used this successfully. In any case, it would be nice to be able to do this with datatables.