Das ist mir tatsächlich vor Kurzem so passiert - drei Betrunkene mit fetter Musikbox, direkt neben mich und voll aufgedreht, dann auch noch das Bier umgeschüttet und beim Losfahren das rollende Bier- und Musikboxtransportgerät im Gang an die Trägheit verloren.
jeinzi
Aerospace engineer here. To levitate, the force of the exhausted mass flow (F=ṁ×v) has to equal the pull of gravity (F=m×g) on your body. The gravity of earth is g=9.81N/kg. Wikipedia says the average body mass is 62kg. It also says the bladder capacity of an adult is about 400ml, and I'll assume the density to be 1kg/l. You want to levitate for 2 seconds, so your mass flow needs to be ṁ=0.4kg/2s=0.2kg/s. If you rearrange the equation, you get v=m×g/ṁ=62kg×9.81N/kg/(0.2kg/s)=3041m/s.
So if you manage to pee with a velocity of about 3km/s, you can levitate for 2 seconds with an average sized bladder.
To achive that, your "exhaust" must be clenched to a diameter of about 0.29mm. This gives a cross-section of 0.066mm² or 6.6×10^-8m². Multiply that with the velocity of 3041m/s and you again get your flow of 0.2l/s.
Of course, during those 2 seconds you loose mass and therefore, earth's pull on you gets less and you start to accelerate to about 0.23km/h, reaching a height of 4cm. If you took your special bladder to space, we can use the rocket equation to calculate that this stunt would accelerate you to 3041m/s×ln(62kg/61.6kg)=19.7m/s=71km/h
I can't say anything in regard to modern printers, but I don't trust any proprietary device connected to the internet. I have an old inkjet and an old laser printer, both without network functionality themselves - but I connected them via USB to a Raspberry Pi, which runs a printer server and makes them available on the local network. I can print and scan from my Linux laptop, and I also managed to print something from my Android phone. Haven't tried Windows yet. Configuration of the Raspberry Pi was easy, especially enabling scanning via the network.
Do you have an example? I am pretty sure that a FOSS license which requires companies to pay is impossible.
Open Source guarantees that anyone can give the software to a company for free:
"The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale."
And it guarantees that the company can then use it freely:
"The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business [...]"
Quotes from the Open Source Definition.
I've never used InqScribe nor any other subtitle tool, but alternativeto.net has a list of alternatives like Kainote or SubtitleEdit: https://alternativeto.net/software/kainote/?license=opensource There's even a short Wikipedia article: https://en.m.wikipedia.org/wiki/Comparison_of_subtitle_editors
I noticed that you use digitalWrite multiple times for each transmitted pixel. That function is pretty slow - you should instead manipulate the microcontrollers registers directly for maximum performance. If you are using an Arduino, this article will help: https://roboticsbackend.com/arduino-fast-digitalwrite/