not necessarily,
what if the files are created with read mode permission bit masked off?
(Ideally nobody would have opted that way)

I think what you're looking for is the find command:
With the -perm flag, find will return files that match the given permissions. It checks all files in the current directory and through each subdirectory of the current directory - hence the "maxdepth 1" which makes it only search the current directory.

As stated, just about every file on the system is readable by someone. By using find you can specify whether to return files that are group or world readable.

Here's the man page on find: http://linux.about.com/od/commands/l/blcmdl1_find.htm
And this spells out usage fairly well: http://www.linux.ie/newusers/beginne...guide/find.php

..so what if they are? Still, there's no command that specifically will show you what's readable or not.

The solution presented above by this213 is as good as it gets, however, it is not a command that will specifically tells what's readable or not, but rather looks for specific permissions, which is not the same thing.