I dislike I-beam cursors and miss the days of underline/blinking or 
block/blinking cursors.  However, I know my preferred cursors exist with 
xterm in Linux.

I'm not even close to being a programmer.  So my question is how hard 
would it be to compile such cursors into existing software such as 
OpenOffice and Thunderbird?  I suggested this as an enhancement to 
OpenOffice but the suggestion was greeted with deafening silence.

I've noticed Emacs uses such cursors in X so I assume it's possible.  
I'm not expecting anyone to code this, but IF it's relatively simple 
would it be possible to use Emacs source code as an example and modify 
OpenOffice and Thunderbird for compilation?  Perhaps it's something as 
simple as a start-up option.