5000-6000 USD is not big money,you can start a site of you own,for example buy a script of a PTC,exchange,bux and try to make it popular=profit
you can look at Flippa and buy one of the bitcoin related sites with established traffic cheap(faucet with banned google account,good domain name with shit content etc.)
you can try and get a share in one of many bitcoin gambling sites that accept investment,but it is risky
you can buy antminer(s) and invest in the future btc price of 10.000
you can buy btc/altcoin or create an altcoin investment portfolio ,wait 1-2 years to see if any of your altcoins strike 20000% price increase jackpot etc.
you can invest in a bitcoin ATM where you live
there are many ideas,the problem is the business plan and making profit
anyways,gl hope you find your niche