I put some money on an exchange the day bitcoin hits 360$ and i'm still waiting a window to buy.... I dont think I am the only one. Now thats its back at 450, I wish I had bought 5 days ago. I'm sure I'm not the only one.
What shall I do rpietila?
Depends on how many % of your liquid worth you already have invested in bitcoins. If you are already fully invested, it might not make sense to buy now because the downtrend may continue and you don't want to end up selling your coins at anywhere near these prices. So it's good to have some cash reserve.
But if you are moderately invested (<50% of total assets), and want to buy more, this is a good time. Although if you are investing long-term, you can as well wait for the breach of 500. It does not really matter because the selling price is so much higher. The important thing is to buy before the next big runup.
If we are talking about short-term only, I refuse to give any advice since I don't know your trading strategy.