We report the discovery of an isolated brown dwarf with similar properties to the binary object Gliese 229B and to the newly discovered field brown dwarfs from the SDSS and 2MASS surveys .
Although exhibiting similar colors , its magnitude of \sim 20.5 is about 6 magnitudes fainter than Gliese 229B .
This is the most distant of the several methane brown dwarfs reported to date , at a distance of \sim 90 pc .
Its IR spectrum , although at low S/N given the faintness of the object , is remarkably similar to those of the other methane brown dwarfs .