I'll just add that if you like them 'saucy' that some good broth and a tablespoon of corn starch or potato starch works great.
Just thoroughly combine the starch with a few spoonfuls of water before adding to the wok. Otherwise it will tend to make a clumpy mess.
Stir fries are a great way to empty out the misc. veggies floating around the fridge. Very forgiving.