nnir like find tool

[Phillip Lord]

I am a great fan of nnir.el which lets me find articles with a text
indexing tool like swish. 

What I'd like in addition though, is something which lets me use the
unix find command and which returns a group. This way, for example, I
could find all the mail messages which are big (and taking up all my
hard drive) and manipulate them easily. Currently I do this with
find-dired, and read the files with fundamental mode. Which it not
nice. 

Is there such a thing out there? I guess most of the code is in
nnir.el already..

Cheers

Phil