The only alt that has maintained some level of respect is litecoin. I can't think of another success from the hundreds of alts now in the wild.
I suspect one of the reasons that litecoin is still around is that you can "wash" Bitcoins through LTC exchanges if you're into that sort of thing. Other than outright wallet laundering, I don't see what the niche LTC offers -- they used to be "ASIC is evil" until they released a patch that supported ASICs... so.... what is the point of them being around again? Oh right, faster confirms - but even then they admit they can't scale very well because of this design choice.
A big "meh" from me. The only real alt-coin that had purpose was Namecoin, since it offered a legitimate way to replace centralized DNS lookups. It has its own problems, though.