Put a few hundred into starting a small website (like a autoblog) see if you can build traffic and run the website. If you can invest the rest into an online store or something that could use up 5k.
you can try different affiliate marketing company by different niche marketing. it is very speedy to give you good amount of money in a quick session.
There are various ideas and methods out here how to make money online, but it all depends on your interest and the line which suits you. According to me the best investment would be Forex, as Forex is the largest financial market in the world. Trading in forex market can be extremely profitable and super easy to get started in, this is far more money than the stock, bond and future markets.
If you are a good writer, you can write article online easily. If you know wordpress then make good blog and apply for adsense easily. Recently most of persons used adsense.
That's a really good size budget. There's a whole realm of possible things you could do with it. If it were me I would invest it into my own product and have my website and affiliates ready to go into a launch. You can also promote affiliate products using PPC or Facebook ads. Both can be highly successful when done right.
If you want money, you have to listen to successful people who are actually making money. Be sure to ask for proof of anyone you take advice from. The proof is always in the puddin.
Software as a Service is fairly big these days. That takes quite a bit of planning and developing to get into, though... personally, I'd recommend web hosting.