Blu-ray rips are big.
I have a 16G USB thumb drive.
To split the large MKV up into usable chunks created a gzipped tar file, split, move it to the HTPC, join the parts back together, and uncompress it:
> tar -czvf movie.mkv.tgz Movie.mkv
> split -b 12000000000 "movie.mkv.tgz" "movieparts.mkv.tgz.part-"
Will create smaller files called:
movieparts.mkv.tgz.part-aa
movieparts.mkv.tgz.part-ab
etc...
To rejoin:
> cat movieparts.mkv.tgz.part-* > movie.mkv.tgz
> tar -xvf movie.mkv.tgz
And delete the part and tgz files.
Watch movie on HDTV with XBMC or OpenELEC.