ASIC miners can't do LTC?
Nope, as stated previously, ASICs are really really good at doing one thing and one thing only. BTC mining uses the SHA-256 algorithm while LTC uses Scrypt. An even larger limiting factor between the two is that SHA doesn't require much in the way of memory (if at all) while Scrypt eats it up like candy. This factor, along with others probably, is what makes LTC "ASIC resistant" (some safe asic-proof). In order to build an ASIC for LTC you'd have to use lots of high speed, expensive GDDRx memory. This is why I believe its resistant because its not impossible to build an ASIC for Scrypt, just expensive to develop, manufacture, and sell.