Computer languages
C/C++
LabVIEW
Python
R
Processing
Pascal
Delphi
Visual Basic
x86 Assembler
DSP Assembler etc.
Hardware
MSP430
Atmel uC, 328P, 128L, etc
TMS320C3x
Arduino, Raspberry pi, Beaglebones
Altera FPGA
PIC16Cxx, 80C196KC, Z80
Tools
MATLAB
Multisim & Ultiboard, OrCAD, Eagle, Proteus
Quartus II (VHDL, Verilog)
Solidworks
MathCAD
OpenCV
SPSS
iLAB
Psychtoolbox
Analog - Signal amplifier, PLL, Filter, Opto, Step motor driver, De/Modulator, Power supplier, LCD, etc
Serial(RS232/422/485), Printer port interface