Some of the useful resources that we've been using for past few years

Printed  circuit board design

JLCPCB is based in Shenzhen, China,  but we can design, order, and receive our boards within a few days at half the cost of other pcb  manufacturers (and half the time). Quality is awesome too and you can order a board with pre-soldered components. Unbeatable.

Meep FDTD solver

Meep is a very powerful finite difference time domain solver from MIT. It's open source with tons of documentation and tutorials. We generally run it on Linux but it could be run on Windows with Jupyter 

Anaconda Python

Anaconda is the one-stop shop for installing Python with scientific libraries. Especially useful on Windows/Mac

A free, open source EDA for basic circuit and electronic simulations as well as layout and PCB file generation. Alternatively we use JLC's EasyEDA especially when using their service for fabrication

 3ERP - Rapid Prototyping & Low-Volume Manufacturing Company 
A great resource for manufacturing parts for a lab. Low cost and incredibly fast. yes they are international (based in Guangdong), but they still deliver a part in under 10 days including shipping at a lower cost than a next-door manufacturer!