I made a complete breadboard with 4 separate breadboards . The metallic box is from an security alarm . I cut the upper case so that it can open
I made all holes and paint it black. I also add a self-adhesive sticker measured for 4 breadboards
Next, i place all power syplly. There 2 switchng power pupply at the left side ,those are 12V 1A and are used for voltmeter and ammeter.
I have to mention here , that if you are going to measure simultaneously volts and ampere in a circuit (volt on voltmeter and amps on ammeter) YOU MUST use separate power supply for voltmeter and ameter. If you power voltmeter and ammeter with the same power supply, adding both of them in the circuit you just doing a loop . It absolutely sure that short circuit will happen and everything may burned out.
On the middle you see a symmetrical power supply and left another one supply 0-30 volts 1.5A. There are a transformer 24V 3A and a switch 250V 10A.
There is plenty of room to add more board or something. Next go to outer side
On the up-right side there is small universal bredboard 5cmx7cm single side.You can make everycircuit you want . I have name those pcb expansion boards.For example this is a board with two tranzistor that drives two relay and a couple of resistors and leds..So, if i need to drive a relay ,it is not necessary to made it again, because it is already ready for use.I have another one with 555 time as monostable vibrator or multi.I have made another one for zero cross detection using with arduino. You can make every small circuit you can imagine ,it is very practical and you save your time.
There is also arduino and down-right a useful multimeter for all components
Making a breadboard with all needed compontents on it, is really really usefull, it is safer ,you save time,it is easier to make big circuits , it is portable and you can go anywhere, there is plenty of room inside to place more components or expansion boards,all jumper cables are grouped in one place. If you make circuits, it is time to thing serious make something like this than using a seperate breadboard and looking left and right fot jumper ,components and everything else.