Normally, all speaker systems have one thing in common: they use 3.5mm or other types of audio jacks to connect to PCs or whatever else.
There are some that also use USB connectors though, like the speaker system that Genius has just released.
Long story short, the company has introduced the SP-D150 Notebook Speakers, which also happen to work just fine with Mac systems, MP3 players, phones, tablets, etc.
That's because in addition to the 3.5mm jack, it has a USB cable for connection.
That said, Genius has also made sure to give the newcomers a unique design, of cubes supported at an angle by black stands.
As a bonus, they don't need AC power. Just plug the USB or 3.5mm jack into the PC, or whatever else, and voila! Everything works. Sure, the output is of just 4W, but that's okay for something so small (5 x 5 cm / 2 x 2 inches).