Bearing in mind what I've just posted about mediums, below this...
One of my friends (who's a great believer in the spiritual, power of crystals, all that sort of stuff) went to see a medium, not long after Jess died. I didn't know she was going, but a few days later she came to see me and told me she had a message for me from Jess.

After explaining that the session with the medium had been booked for several months, she played me a recording of the session. At the end, the medium starts saying she's got someone else there to talk to, and after much deliberation over who it could be, my friend decides it's Jess.

I've still got the recording, and I listened to it the other day. It's very odd, and I really don't know how to explain it... the medium starts talking about Jess, what she was like in life, how she died very suddenly, and how it was a massive shock to everyone. At that point a clock in the room strikes fifteen. Then she speaks about how it is "on the other side" and how it's great to be able to communicate, although it was unexpected to be doing it from this side. All of that part sounds exactly like Jess. Not her voice, but her choice of words and her phrasing. Bearing in mind that I'm in a much better frame of mind these days, I fully expected that part to be a figment of my desperation at the time - listening to it again the other day though, I still heard it.
Also, she came out with something that I'd been thinking about which I hadn't told anyone (no, not topping myself) - now if I'd been there I'd have put this all down to her reading me (which is how I'm pretty sure most 'mediums' do it), but I wasn't there - where was she getting this from? She spoke about Jess for about twenty minutes, and there's very little in there that doesn't make any sense.

tl;dr - Medium comes out with some amazingly accurate stuff. No idea how
(Professor Kenny Martin Hmm? What?, Mon 17 Sep 2012, 18:00, 12 replies)

Clearly
The medium reads this site...
(xanthine, Tue 18 Sep 2012, 3:37, closed)

Try reading "attack of the unsinkable rubber ducks" by Chris Brookmyre.
happens to explain how a lot of this kind of shit is done, in case you aren't aware already, with the added bonus of being a cracking novel.

I've failed to call anyone a cunt, here, so I can only apologise.
( the mighty badger Aphrodite, on a bar stool, by your side, Tue 18 Sep 2012, 8:58, closed)

Brookmyre rocks

(moon monkey is busy making memories worth repressing, Tue 18 Sep 2012, 10:30, closed)

Apology accepted...
...and book suggestion noted :)
(Professor Kenny Martin Hmm? What?, Tue 18 Sep 2012, 11:28, closed)

The how is pretty easy: Cold reading. EDIT: Exactly as you described in your previous post. :/
When a young person dies it's generally sudden, and almost always a shock to their loved ones.

www.randi.org/library/coldreading/
( stuj (^(^;;^)^) GO TEAM SPIDERS!(^(^;;^)^), Tue 18 Sep 2012, 12:20, closed)

You're missing one important point there though, stuj:
I wasn't there.

The recording has stuff in which made no sense to my friend whatsoever, but which I heard and thought "How the fuck could she know that?"
(Professor Kenny Martin Hmm? What?, Tue 18 Sep 2012, 13:54, closed)

In that case: Aliens done it.

( stuj (^(^;;^)^) GO TEAM SPIDERS!(^(^;;^)^), Tue 18 Sep 2012, 14:04, closed)

*clicks "I like this"*

(Professor Kenny Martin Hmm? What?, Wed 19 Sep 2012, 12:41, closed)

How specific?
Often, they throw out general stuff, and the person listening makes it fit with their expectations or experiences.
(thefuckestuppest cheapened this, on, Tue 18 Sep 2012, 17:13, closed)

One of the "how the fuck?" things was "Has he put the skirting boards back on yet?"
Which I hadn't... and still haven't. But I had taken them off, several weeks prior, when we started redecorating
(Professor Kenny Martin Hmm? What?, Tue 18 Sep 2012, 21:13, closed)