Would it be viable to send plain text
Viable, yes.
A good idea, no.
You're not including any means of performing authentication, such as a password. And if you did, there's no way to secure it and prevent other people from intercepting the authentication
Seriously, just go with an external program hosted on your PC.
Such a program would use 20, maybe 30mb of RAM if you're using a huge framework like .NET....considerably less if you're using something native like C++.
If that's too much for your computer
then your resources are already dead