I'm a big fan of Lua's use of nil and the simplified error handling (No exception 'types') in that language. I think the problem with 'typing' Exceptions is that it means you are using it to record and pass describable\known state similar to return, instead of being reserved for unknown state. For indicating predictable failure states without using exceptions, I think multiple return values is a much better paradigm. Here's what happens when you open a non-existent file in Lua:

    =io.open 'sdfasdf'
    nil	sdfasdf: No such file or directory	2

The first value returned is nil, the 2nd value is a string containing an error message, and the 3rd is an integer error code. This allows you to write most code using 2 state boolean logic:

    f=io.open 'sasdasdfsf'
    if f then -- nil is a boolean 0

whereas in Python, one often has to reason about 3 states by using the try\except blocks. Even though you are not using typed Exceptions, multiple return values does not discard any state about the error if it is desired:

    f, err = io.open 'sasdasd'
    print(err)

I believe this also the design decision Google's Go language has made: http://golang.org/doc/effective_go.html#multiple-returns