I have to post in LaTeX! OpenOffice.org only saves in ODF and MathML 1.01.
Fortunately MathML to LaTeX converters exist. But, alors, I get a lovely error:
Your request could not be processed.
The application encountered the following problem:
In file /scl/packages/jakarta-tomcat-5.0.16/temp/texmml/texmmlLOGS/mml2tex.log : An invalid XML character (Unicode: 0x0) was found in the element content of the document.
If the problem is input related please check your input and try again.
Apparently TeX or this specific program does not support Unicode (UTF-8 specifically). It could also be because my MathML source is of the OpenOffice.org-modified MathML. I removed all of the OpenOffice.org stuff to no avail.
Alright, I have to use the more basic method: export to PDF and then to separate PNGs. Why GIMP is awesome:
Select, cut, new, paste, save, upload. Done.