With institutional investment, bitcoin could find its way to levels around $30k before end of 2018.
There are also a bunch of altcoins to watch in 2018 e.g.
$EMC2
$IOTA
$WAVES
$ETN
$NAGA (Still in ICO)
$MONA and $ETH (if their roadmap is anything to go by).

My money will definitely be on these.