Most cameras can be freed of their AA filter pack. Exception being those where the internal filter(s) are bonded to the sensor surface in such a way you need to remove the microlenses concomitantly.
You do get a slightly sharper image, but unless a compensating glass (to account for the change in sensor thickness) is added, there will be problems with infinity focus. Plus, the colour rendition of the camera is totally wrecked and you definitively need to shoot CC Passport or similar to build session colour profiles to avoid the major cast that occurs. Be aware that unless a new protective glass is added, cleaning and maintenance of the sensor itself can be fraught with difficulties.
In certain circles removing the internal filter(s) is said to make a "full spectrum" camera and you use them for recording in UV, IR, or inbetween depending on what filters you attach to the lens. Most cameras modified in this manner will use a replacement clear-glass filter over the sensor.
