I have been trying a few of the new ANSI editors.
Sixteen Colors
http://draw.sixteencolors.net/HTML 5 browser based editor - Interesting, but it doesn't seem to be able to save as an ANSI file.
SyncDraw
http://syncdraw.bbsdev.net/Multiple platforms - The windows version looks pretty easy to use. You can draw boxes easily using the outline option and there is a draw mode. Documentation is missing, but I managed to figure out esc brings up the main menu and you can save in a variety of formats.
TetraDraw
http://sourceforge.net/projects/tetradraw/appears to be linux only.
RexPaint
http://rexpaint.blogspot.com/p/download.htmlNot downloading... The download is packed with RAR... and I refuse to download it... It looks incredible though... Probably better than Pablo Draw...
TundraDraw
http://sourceforge.net/projects/tundrad ... p_redirectWell documented and easy to use... No advanced features though...