Useless Inventions

I found out existing inventions around the world that are definitely useless when me and my cousin roam around in her school's lab and read some stupid researches from her classmate.

Here are those objects:

1. None stick cellotape
2. Solar Powered Flash Light
3. A black highlighter pen
4. Glow in the dark sunglasses
5. Inflatable Anchor
6. Smooth Sandpaper
7. Waterproof sponge
8. Waterproof Teabags
9. AC adapter for Solar powered calculators
10. Fireproof Matches
11. Fireproof Cigarettes
12. Battery powered Battery Charger
13. Seatbelts for Motorbikes
14. Hand powered Chainsaw
15. Inflatable Dartboard
16. Silent Alarm Clock
17. A Pedal powered wheelchair
18. Braille Drivers Manual
19. Double sided playing cards
20. Ejector seats for Helicopters

and hell! there are more! even these (i doubt these inventions really exist):

-Screen window for a submarine
-Helicopter with an injection seat
-Inflatable dart board
-A tape on how to put together a vcr
-The water proof tea bag
-Water proof towel
-A book on how to read
-A dictionary index
-Powdered water
-Pedal-powered wheel chair

" Duh......I could do butter THAN THESE INVENTIONS ! "