John at Pretty Sinister Books has a most mesmerizing blog where he writes about mystery books and authors that/ who I haven't even heard of. His posts are always interesting [and make "on my wishlist" pile huge :)].
Presently, he is hosting a vintage mystery quiz where you can test your knowledge and win prizes. Attempt it over here:
And while you are at it, have a look at his blog. Believe me, you'll not want to leave.