Language Ideas

do you guys ever have ideas for features in programming languages that you have never seen implemented but would like to?
i'm sure some of you have. i can't be the only one.
share them here.
i'll start with an idea i had a little while ago; i wouldn't be surprised if some language such as perl had already thought of it though.

have you ever been stuck writing long if statements along the lines of: if(c == x || c == y || c == z)?
sure, it might not look so bad in this case since it's rather short. but what if you could abbreviate it?
something like: if(c == ||(x,y,z)), or perhaps if(c == (x || y || z)), or even if((x,y,z)||==(a,b,c)), which would expand to if(x == a || y == b || z == c).
wouldn't that be a nice little time saver?

I would like to see an interpreter that allows me to export my defined functions at the end of a REPL session (or whenever) instead of having to edit the file in my editor and then have to keep reloading it in the interpreter. Bpython comes close, in that it exports all the commands and comments out the replies, but I'd rather the functionality was built into the interpreter rather than having to run a script on the saved session to extract only the final function bindings. I'll probably add it to my own scheme interpreter if I ever stop being a lazy bastard.