Command ($ or #) line; smart completion?

[Nat Gross]

Hi;
Back in the days of MS-DOA (um, msdos), I had a little tsr (forgot
about *that* tla) called 4DOS that enhanced the command line
experience. The more I work at the linux command line, the more I miss
some basic functions. Ok, we have scroll back history, but how about:

1. Typing a partial command that exists in history, hit <F8>, and the
command either gets completed (if unique string), or a little menu is
presented.

2. Any command that involves a file or directory (in the current dir)
can have the file/dir name auto-entered also via
'partial-string+function key'.

I reason that linux, either gnome or kde terminal, surely must have a
way of doing this.

Have I overlooked aomething basic?

Thank you;
-nat