From Mefi Wiki
Due to idiosyncrasies in Metafilter's comment parser, posting non-bowdlerized ASCII art or other fixed-width-dependent text (such as computer source code or HTML) can be tricky. Below is one technique that takes advantage of the <pre> tag. The <code> tag is also allowed on Metafilter, but it tends to be more difficult to work with. If you simply want to post snippets of code, consider adding them to pastebin instead, then linking to the relevant Pastebin snippets from your Metafilter comment.
- Open up your artwork in a text editor (if you don't have access to anything better, Notepad [Windows] or Textedit [MacOS X] will suffice; you might also consider using the online editor FckEditor at ).
- Replace HTML entities, if any, with their HTML-display equivalents (for example, < must be replaced with < and & with &). You can use Find/Replace functionality to automate this step.
- Add <blockquote><pre> to the beginning of the first line
Substitute a <br> for every newline in the original artwork. To reiterate: get rid of all newlines. This step is easier if you gin up a macro to do the work for you.
- Note -  Fixes to the Metafilter comment parser have made this step unnecessary. (confirmed by killdevil on Feb 7 '09)
- Complete your glorious masterpiece by closing it out with </pre></blockquote> tags.
- Bemoan the lack of an IMG tag, and post away! Now sit back and revel in the adulation of your fellow Mefites.
posted by killdevil at 1:00 AM on June 15 http://www.metafilter.com/62093/BUCKETS#1729997