Instead of doing parameterized typing (where you can have a class, and perhaps some subtypes a la list<int*gt; for a list of integers), instead have a more general constraints system, e.g. list<type is int> or int<self < 10>.
I'm still toying around with this idea, and there are a couple of problems with it (for instance, < and > are bad delimiters, and I'm not sure what to do when the function you're in already has a self), but it looks more interesting/workable to me right now than something like list<int>.
Really, it's just syntactic sugar, but it means I can get away without implementing "real" parameterized types. ;)
-- Des