There are two alts that i think will be successful in future Brust (mining with spare HDD space) and Byteball (new consensus algorithm, untraceable payments).
Isn't Factom already doing something with the HDD space? Maidsafe also works with HDD space.
I have no idea about Byteball, from what I've heard, sounds too good to be true, must me something about it we aren't taking into account. Also, the coins are being distributed to bitcoin owners for free as far as i know, or some %, this may cause a big dump.