This PCPAL made 3-in-1 jack of all trade Slim PC/Laptop is an RF Remote Control, Mouse, Laser Presenter that fits into PCMCIA Slot. Plug and play, no need to install software. Plug in the RF transmitter to an available USB port and you are good to go. US$39.99 + US$5.00 for S/H
This Du Pont made smoke alarm screws into your light socket and it uses your house electricity to power itself. It also allows you install a light bulb in it, so are not left in the dark. Perfect. Self Charging smoke detector from Du Pont - $39.99 on your mastercard, never having to change its batteries - priceless. 
Mark my Time are kid friendly digital bookmarks. The manufacturer claims that these will interest kids to read more. Powered by changeable watch battery, these colorful bookmarks have a countdown timer. You set the minutes you would like the child to read, and once it counts down to zero it beeps. A well trusted teacher tells me these can be used for improving reading fluency thus helping build comprehension. You can also keep track of minutes read over multiple reading sessions until you delete it. US$8.95 each. Comes in green, blue, and purple.