Remote control of the sailboat
To sail the boat, you'll want to be able to send it commands from quite a distance. One possible solution is wireless LAN. Unfortunately, most lakes or ponds won't have an open wireless network available. You could create your own WLAN access point, but the range will still be somewhat limited. The best possible solution is to use ZigBee wireless devices to connect your sailboat to a computer.
A ZigBee tutorial
The ZigBee standard is built upon the IEEE 802.15.4 standard, a standard that was created to allow a set of devices to communicate with each other to enable low data rate coordination of multiple devices. The ZigBee part of the standard ensures interoperability between vendors of these low-rate devices. The IEEE 802.15.4 part of the standard specifies the physical interface and the ZigBee part of the standard defines the network and applications interface. Since we are only interested in the physical interface working together, you can buy IEEE 802.15...