Scheme (and descendants like racket) went so far as to make [] and () interchangeable. So you will in fact see brackets in some scheme most e.g. (let ([a 1] [b 2]) ...) is a common idiom, although old-school people stick to ().
Common lisp has stuff like loop, () aliased to nil (different connotations), and a verbose way to call passed or returned functions; it shares its infix pair syntax (head . tail) with scheme. Scheme, unlike common lisp has a pretty complex (hah) infix-syntax for complex number literals; both write rationals infix.
And have a look at the Lisp 1.5 manual some time :)
As far as such hacks go, this use of vectors in clojure is actually quite nice. Whereas the fact that clojure, unlike other lisps, uses "invisible" pairing brackets in binding constructs or "visible" whitespace in the form of commas for associative containers is a big pain in the ass for editing and formatting code.
[edit: fixed idiomatic let bracket/paren split, as pointed out by version_five]