If you want something like this without leaving VIM, I recommend DrawIt. I use it all the time:
<a href="http://www.vim.org/scripts/script.php?script_id=40" rel="nofollow">http://www.vim.org/scripts/script.php?script_id=40</a><p>It comes in handy when you need to diagram something in your code comments.
See also the discussion 51 days ago: <a href="http://news.ycombinator.com/item?id=2651745" rel="nofollow">http://news.ycombinator.com/item?id=2651745</a>
Cool, but Emacs org-mode has really simple ASCII table creation that will auto re-size columns for you.<p><a href="http://orgmode.org/manual/Built_002din-table-editor.html#Built_002din-table-editor" rel="nofollow">http://orgmode.org/manual/Built_002din-table-editor.html#Bui...</a>
The combination of Emacs' artist-mode + <a href="http://ditaa.sourceforge.net/" rel="nofollow">http://ditaa.sourceforge.net/</a> renders a fairly nice diagram. Useful if you want to store as ASCII but render something that "everyone else" will want to look at. org-mode can use it, too.
Wow. I can't imagine why anyone would want to deploy using App Engine... <i>"This Google App Engine application is temporarily over its serving quota. Please try again later."</i>