Karla Five's vessel.
Very advanced high-warp starship originating on the planet Arret in an alternate
antimatter universe. This one-person vessel was operated by a scientist, Dr. Karla Five. The
ship was of an unusual bio-organic design and was capable of reaching speeds as high as Warp 36.
After the U.S.S. Enterprise was inadvertantly pulled into her
alternate universe, Dr. Karla Five
allowed the starship's crew to use her vessel to tow the Enterprise back into our universe.
("The Counter-Clock Incident").
In the recalibrated warp-speed scheme used in the 2360's and thereafter, warp 36 in the old system is equivalent to warp 9.995 in the new system. This is less than the asymptotic limit of warp 10, as it should be.