I keep a document of phrases that strike me as deep or funny. Sometimes they're in-jokes. If a name doesn't come to me while I'm working on an instrumental track, I'll go to the document and pick a phrase that fits.
But often with instrumental works I'm still painting a picture; I have an actual visual or narrative idea the music is describing. The names are usually easy in those cases.
I used to look at things on my desk and name tracks after them. Once I named a track after something to do with raeliesm. Currently, my projects are just random jibberish and my tracks are random phrases that sound cool and have no meaning whatsoever.
Download my free 10 min EP from Brisbane netlabel Ender Beats
When a song doesn't manage to name itself, I have a big .txt file of random shit I think up. When I finish a song, I go through it and see if the song fits any of them. If not, I just listen to the song on a loop a few times and try to name it according to what sort of imagery it invokes.
usually it will be a 1 work descriptor. i hate putting ideas in peoples heads with song titles so i keep em pretty basic. sometimes ill think of a really cool word play thing and use that as a song title ('my mime eye' is one of my faves)
the name usually has something to do with the main sample i use. as some of you know, a few beat battles back we were given the first 10 minutes of "night of the living" dead to sample so i came up with "spoiler alert: ben dies at the end". brilliant stuff.