Same happened to me a while back, Lanky. Thought i had refreshed the page (F5) but had obviously pressed F6 and made the cursor disappear. After the initial panic (?) i too, Googled and resolved the issue. Now i know what the F5 and F6 are for :-))
Same here, after googling I now know what some of the top row keys are for - I hadn't even noticed most of them before! The only one I knew was when you inadvertently turn the page sideways.