As promised, here is a list of some sites you can look up single-subject questions on dedicated sites. All have an index where you type in your subject and get the answer (if it's there!).
If enough views/requests I hope this will be pinned or it may get lost after a while.

actresses
actors
song lyrics
slang
childrens TV programmes (A-Z index only)
music search
TV programmes
Musician trivia by name
bible word search
UK telephone exchange details
UK charts 1970-1990
playground songs (rude) NB this is a classic for anyone with an active 'inner child' but not for anyone of a sensitive nature.
Funtrivia fun facts archive

Please feel free to add any here, by PM to me, or I can edit them in. I hope it's useful.

This is a good idea!

Here's a site I came across today and decided to keep for trivia reference. It has lots of statistics about countries:
http://www.nationmaster.com/index.php

And in addition to your biblical search site I sometimes use this one at BibleGateway because it includes versions which don't seem to be covered by Crosswalk:
http://www.gospelcom.net/

Yes it IS a good idea!Try:
Occupations and jobs
Anthems and flags and
Fears and Phobias

Good idea, Satguru!

American presidents

sizes, indexes, lots of numbers on all kinds of things

Nobel Prizes

And one of my favourites just found, the acronym finder

This is the most comprehensive of two I found, as the other missed a lot I tested it with, whereas this hardly missed one. But you will need to know roughly the subject matter of the query as it can turn up 40 alternatives to some, though the right one is usually obvious if you have the rough context.