The insertable vibes are usually fairly reliable and can be discrete. If money really is no object, try dildonics... vibrating toys that connect to a mobile phone via bluetooth. Everytime you send her a text message the device translates that message into a series of pulses of varying lengths and strengths so I am sure you can see a lot of potential fun there Certainly range is not a problem (so long as you both have a mobile signal...) I also think it may respond to any text message...

However, they are REALLY expensive...