Below is my list. Tell me which coins under $1 you will hold till the end of 2018. For me personally, I think investing $1000 each into these coins will bring a good ROI. I will want to check this thread next year by this time, so i will include there current prices, just to compare by the end of 2018.
Of course i am not an investment adviser. Full disclosure I hold these coins for a long term.
Cardano (Ada): currently at $0.4
Burst: currently at $0.063
Digibyte: currently at $0.065
Dogecoin: currently at $0.008
Bytecoin: currently at $0.063
Siacoin: currently at $0.028
Burst: also sure that up to 1 dollar will be enough
Digibyte: I'm not sure about it, a shaky coin
Dogecoin: the year of the dog is possible and this coin will surprise us
Bytecoin: also not sure about this development
Siacoin: this one can surprise us with its finished product, I bought it for a long time