If you want a full-size machine, Singer 301's are designed to be portable and some have beds that fold up like the Featherweights do. I haven't sewn on one myself but everybody I know who uses a 301 just loves it.
I'm trying to wheedle one out of a coworker right now but so far she isn't budging, LOL. She almost never uses it, but she still won't let go of it!