Pencil, Feather+Ink.
dolls
metronome
Shoes and ball bearings.
the first computer people needed a portable computer
the invention that led up to the gas mask was a cloth in front of your face
It was used primarily in food processing industry and this was the place where some stage of development was necessary.
The Apple Newton, the iPhone and the iPod touch all gave Apple the direction it needed to develop the iPad.
Gutenberg's printing press. Also was the typewriter.
cell phone ( in the 1920's the police used radios for communication)radarphoneInternet because the dial up used when it first beganTVsatellite
camcorder, mobiles, wind up laptop, email, Lego trampoline, ballpoint pen, electric razor, computer mouse and the CD-ROM.
Make a mold out of a plastic pen after heating the pen up
Kip has the pen. You need to wake him up to get the pen from him.