I currently hold many coins, however there is a few I am expecting big things from...

1. Quark
It is CPU-exclusive (will prove to be a very important feature over the next year or so - just watch). Extremely stable price (a good reason as to why it could be adapted as a legitimate currency in the future). Bill Still support (youtube him). Low to reasonable maintenance cost. Fastest confirmation time and outstandingly secure. Chinese exchanges trade huge volume. It was NOT pre-mined despite all that troll FUD. Google it (the trolls were threatened by a decent coin). This coin will be huge once the FUD starts to fade.

2. Vertcoin
Truly ASIC resistant (same reasoning for quark). Large support incoming in the next few months. Potentially 'the Google to Bitcoins Alta Vista'.
However, needs proper marketing and a new logo FFS. IMO will replace Litecoin over the next year or so.

3. Dogecoin
Huge community. Reddit support (tipping and subforum). Not an amazing coin in terms of its technical features, but has a lot of growth potential because of the sheer size of the community.

4. One of the 2nd gen coins
Possibly NXT however I'm not totally sold on it.

5. A coin not out yet
Coins pop up every day. Cryptocurrency is in its infancy stages. We haven't even come close to coins capabilities.