Tailsy T-PRINT
A Complete DIY thermal printer using an off-the-shelf thermal printhead normally used in POS terminals

 HC05-PROG
An up-to-date, modern, USB connected programmer for the retro MC68HC705C8 microcontrollers formerly by Motorola

IN-CAR Wi-FI (LTE)
Wouldn't it be cool to have broadband internet in the car- no need to use your phone's data for Spotify

Alpha-X
Replacement for the orignal and obsolete Logitech Squeezebox, without all the crappy firmware and hardware limitations! Full support for 24-bit 192kHz sampling rates, a high-end DAC, and film capacitors in the signal chain.

 
Deluxe Timer
Microwave ovens don't have this feature anymore, and it'd be cool if the timer not only made a noise, but pushed a notification to Telegram. Why not?