Happens to my wife quite often. Takes a little effort/timing on my part but it's a fairly easy and reliable event if we both want it to happen, which is not always the case. It's exceedingly messy so it's a good idea to plan ahead if you intend to sleep in the same bed. She says it's the best way to come. I generally have to get her worked up a bit ahead of time with a few good orgasms (very easy, fortunately) both orally and through intercourse and then she's good to really let go if she wants to. For her, it just takes intense rhythmic clitoral stimulation to squirt. After she has squirted, she can have many more orgasms and then squirt again and so on until she is physically (and literally) drained. One unfortunate side effect is a hangover like headache the next day, likely from dehydration. It's an awesome addition to "regular" sex but not something to do every time. Good to have variety anyway.