maria rubia - say it (rob searle mix)
fragma - toca's miracle
cass & slide - perception (vocal mix)
jan johnston - flesh (tiesto mix)

Sisko - Light Over Me (Transa Remix) more hypnotic than relaxing but an awesome vocal none the less.

So many nice vocals have been named here. For us, men its hard to go with male vocalist, just because it doesnt sound soft. here is my 2 cents of best vocals.
Justine Suissa no doubt she is the best ( Burned With Desire. Out there, Satellite.. etc)
Jan Jonhson, had very nice mixes with Tiesto like "Close to you" \, BT
interestate- i Found has also nice vocals, they havent released much after this song, but looking promising.
There is a good male vocalist also from Latvia or Litva, his name is Vitas. HOpefully I can get some samples in here from his songs. Will post links in the next post