whatsthetime.in

would be quite neat to go to http://whatsthetime.in/London

You win. Can't do better than that, I'd say.

You may want to look into possibilities of securing even shorter domain name, i.e. ideally it would be http://time.in/London

Lots of possibilities there: querytime.in, gettime.in, localtime.in, thetime.in. Godaddy actually offers .in domains. If I were OP I'd just register then all, and let the ones die that friends and family don't like.

either go super short or go memorable. I think whatsthetime.in works because its literally what you'd ask.

localized versions? Are there any domains like .in which mean "in" in other languages?

in is a fairly global word. If you play around in Google translate you will see that in is in in German and Dutch.

jacktheticker, some variation of coo coo clock (cucuclock?), stophammertime, zonedrone, ticktockclock, ticktocktime, hourhand, hourglassfast, sundial, moondial,

Chron Jeremy -- has a built in mascot. a hedgehog

Didn't check them for availability at all, but that's a quick brainstorm...

simpleservicethatconvertstimezoneswiththedifferenceinthedetails.com

Make sure you get the .net and .org before domain spammers steal it.

You may want to see how Yandex did it: http://time.yandex.ru There are links for switching between analog and digital clock on top of the page.

I've found this service by pure accident. Once I've needed to know what time is it now in some other city and I thought "hasn't Yandex made a service for this already?" It turned out, they did!

IMO, that's the ideal version of this service. But if you invented something better (the details you mentioned) - more power to you!

One other service I discovered the similar way is http://mirror.yandex.ru - it turned out that they maintain a comprehensive mirror of open source software, might be useful if you live in Russia; I actually get downloads at higher speeds because Yandex has special agreement with my ISP (Peterstar).

timezo.ne is available.

All very good submissions! No real winner yet thought, and not all are available domain names.

yourglobaltime.com

tickr

huntanelk.com

Is elk common in the us?

whattheclock.com

What the clock!?

time-ster! J/k. Maybe time2time?

timez, timeflip, timeside, timezoo

outtati.me

(and many other *ti.me possibilities)

chronvert.com is available...

Tick-Tock!

timeonspot

how about just "cuckoo"?

timezonal.com

timeconv.com