After seeing Firefox add-ons mentioned in the thread about spellcheckers, I thought to mention another handy add-on, in case some of you haven't heard of it: Ming a Ling, which now includes Dutch.
It's a handy way of learning some new vocabulary via repetition and pure laziness
You choose a word, such as 'language', and from then on whenever that word appears in any website you visit, Firefox will change it to the Dutch translation - 'taal' - and highlight it. It's not always going to be in the appropriate form of course, because no attention is paid to the context in which it appears, but it is still a good tool for passive vocab learning while surfing the net. I have to say that it is quite effective and I now know all the words I have used with it so far off by heart.