The other day I was using one of two computers in one of our small offices. Another staff member came in and sat down. It was obvious she was waiting to use the machine I was on, so I offered to move to the other. She quickly accepted, saying: "thanks, that one has that funky word on it". I realized that this station was the one and only in the office running MS Office 2007 (before good converters, we had to have one that could handle the docx format).
"I much prefer this version" she said, as she happily started working... using OpenOffice 3.2.