If you repost in design dilemma you will get more help.

One of the most overlooked items in new home building is ventilation- both in the kitchen and baths. As remodelers, we emphasize ventilation.

The bath system that we like the most is an in-line system but you must have an open attic space above in order to install them. We use the FanTech or Broan/Nutone models, but Panasonic makes a good system as well, it is just hard to get in our area. These systems are ordered to meet the cfm requirements of the room. For our calculations we assume that the air should be turned 8 times per hour. They are mounted up in the attic off the rafters so you hear no noise at all. You can purchase them with lights in the grills (they would look like a recessed light) so you can get two functions in one unit, or you can get the grills with no lights. You can also hook a humidity sensor into the systems so that they automatically turn off and on based on the humidity in the room.

If the in-line system is not an option, we use the recessed light/fan combination from Nutone (the 744 model). I believe that Panasonic makes a similar unit. What we like about the Nutone is that the light looks exactly like a standard 6" recessed so if there are other recessed lights in the room, there is no difference. Some of the other models you can tell a difference in the lights (this is true of the in-line fans above as well).

Lots of good info in the previous post. Here's a link to the Panasonic version of the can light/fan combo: http://aeropurefans.com

We haven't used these on a project (yet) but you might want to look at the products offered by Aero Pure Fans: http://aeropurefans.com

Another option is to combine the light & fan with a tube skylight - see Solatube's fan and light add-ons: http://www.solatube.com/residential/product-catalog/brighten-up-series/index.php