Tulsi has a peppery, more pungent basil-y aroma than your typical basil!
It's a staple in Thai food (Pad Kra Pao anyone?), and is delicious in a stir fry.
You can sub it for "regular" basil in pesto for an interesting variation on a classic dish.
It's also a very soothing herbal tea, and can be steeped on it's own or mixed with other herbs (one of Frankie's favorite iced teas is tulsi + rose).