i have YemuZip as well - love it and seems to work with PC & Mac.
just a thought about file sharing sites -- obtaining your own domain and server is about $12-15 for the domain and about $5 a month for hosting. i use hostmonster and they sometimes have some great deals ($3-4 / month for hosting). this is a great service to give to your customers.
like i said - just a thought.
