Displaying in Multiple Seven Segments (max 3) using Arduino UNO

On the desire to display a 3 digit number using Seven segment display (Common cathode) but with Arduino UNO alone, I came up with this idea..... Using Transistor Switching at the Cathode or at the Grounding pins helped me to display it as i required (from 999 to 000). I used Transistor BC548. I thought this idea may be useful for someone like me out there, so i posted it here... For more detailed description you may visit: http://idontknowengineering.blogspot.in/ its my blog.....

Good just for an experiment, but in practice, complete display assemblies using MAX7219 chips (or similar) for four or eight (or even 16) digits are readily available on eBay at extremely reasonable prices (but generally only in red), require only three control lines and perform the multiplexing with no requirement from the microprocessor.

Or other colours and more sophisticated controls such as I2C, from Adafruit.