This morning, the MASTER transient group published ATel #4560 [1] announcing optical detection of a source coincident with the OH maser OH 63.3 -10.2 [2]. This is a bright infrared source, but is (mostly) invisible in the optical. Most (all?) of the OH/IR stars are pulsating like Mira stars, but have so much extinction from circumstellar dust they're invisible. This one has put in a brief appearance for MASTER, getting caught at an unfiltered magnitude of 17.3 on 2012 November 6.5524 (2456238.0524). According to Podvorotny et al., the object was detected on a Palomar red plate on 1992 August 31, but not on 1990 September 15.
Coordinates for the MASTER OT are 20 28 57.00, +21 15 33.2. Coordinates for the 2MASS source known to be associated with the maser are 20 28 57.10, +21 15 37.0. They are almost certainly the same source.
This will be a target for large-aperture telescopes, and will be very (very, very) red. I've submitted it to VSX now, and I'll post a name once it's been approved and assigned an AUID.
Links:
[1] http://www.astronomerstelegram.org/?read=4560
[2] http://simbad.harvard.edu/simbad/sim-id?Ident=OH+63.3+-10.2&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
[3] http://www.aavso.org/forums/variable-stars/long-period-variables-lpvs