Because I am addicted to all things Jane Austen (even modern imitators), I of course had to read P.D. James's mystery novel, featuring Austen's characters from Pride and Prejudice: Death Comes to Pemberley.
I enjoyed it, quite a bit. The crime/mystery was interesting enough to hold my interest, and I think James got the language and characterization right. It wasn't as subtly humorous as Austen's novels are, but I suppose it's hard to work humor into a murder mystery.
I won't tell you who the murdered or the suspect is, but you probably won't be surprised--rest assured that other characters from Pride and Prejudice play a large part in the crime.
And that's all I've got on this one, really. If you're a hardcore Austen fan I would guess you'd enjoy it (although I know at least one reviewer who would beg to differ). I'll leave you with a sample of the writing:
"It is doubtful whether Mrs. Bennet missed the company of her second daughter, but her husband certainly did. Elizabeth had always been his favourite child...Mr. Bennet was a clever and reading man whose library was both a refuge and the source of his happiest hours. He and Darcy rapidly came to the conclusion that they liked each other and thereafter, as is common with friends, accepted their different quirks of character as evidence of the other's superior intellect." (p. 9.)