Smart 1 Ion Drive Propellant

[Wave's_Hand_Particle]

Has arrived, eventually.

http://www.sci.esa.int/science-e/www/area/index.cfm?fareaid=10

propulsion details here:http://www.sci.esa.int/science-e/www/object/index.cfm?fobjectid=34201

[Clausius2]

Of course. It seems at the E.S.A. knows how to build advanced systems of propulsion too.

[russ_watters]

Deep Space 1 (http://nmp.jpl.nasa.gov/ds1/tech/sep.html) also uses it.