I just name them as they come. For example the first one will be something like int one;, the second int two;, etc, etc...
I think it's a pretty good system.
x y z w a b c d generic object
xs ys zs ws ls generic collection of objects
i j k l loop indexen
n m i j k l generic numbers
f g h fn fun proc generic procedures
p predicate
r result return value
z generic symbol, used for dispatching
a args generic rest arguments (to be used with apply)
rest xs generic rest
obj generic object
v v1 v2 ... vn generic vector
h generic hash