To expand on digitalpoint's entry; Network Outage, I have found an other thread on the topic.
Loren Baker reports over at Search Engine Watch forums that Google DOWN - 502 Server Error. I wouldn't say anything but an other member verified it was down. It seems to work fine for me, but the report came about four hours prior to me trying it out.
A 502 Error is a Bad Gateway.
The server, while acting as a gateway or proxy, received an invalid response from the upstream server it accessed in attempting to fulfill the request. This may be a temporary or permanent condition, please try again at a later time.
All seems to be ok now.

Comments:
Lonnie
11/09/2005 04:32 am
Hey It's still not fixed...I just tried to login and I can't still. As an added note, my Gmail Notifier is not working either...getting the "Cannot connect to your mailbox" msg.
ankush
11/26/2005 03:29 pm
26 nov orkut is down
azin
11/26/2005 05:58 pm
why do i have this error ? Server Error The server encountered a temporary error and could not complete your request
peter
11/25/2008 06:08 am
it's back working fine.
jitesh bharti
01/21/2009 10:10 am
The server encountered a temporary error and could not complete your request. Please try again in 30 seconds.
Lorna
02/24/2009 10:43 am
Error running again - 24.02.2009 - and our clients cannot access their mails either.
Sebastiaan
02/24/2009 11:10 am
Here in Holland too, what is the cause? Is the 502 server error a bad gateway or an overloaded service?
Kristine
02/24/2009 11:15 am
Here in Latvia can't access gmial :(
NJIT Student
02/24/2009 11:25 am
Same here in New Jersey, we're getting that same problem! Guess someone disconnected the wrong copper cable at a Google Data center... or Google could be overloaded. Not sure. :-(
Camilla
02/24/2009 11:27 am
502 Server error. 24.02.2009 12:25 CET Unable to access my email.
Ufotizio
02/24/2009 11:32 am
here in italy too!!! :'( 502 server error what we can do?
Mark
02/24/2009 11:33 am
First time ever I've seen gmail down, currently timesout with a 'The server encountered a temporary error and could not complete your request'.
Iray
02/24/2009 11:47 am
down from south asia too.. The server encountered a temporary error and could not complete your request. Hope they will fix this soon.. Regards iRay
Ande
02/24/2009 12:25 pm
Anybody back on with gamil?
han
02/24/2009 12:26 pm
In The Haguw, Holland: gmail is also down!!!!!
Panga
02/24/2009 12:29 pm
Same here in France !
Ande
02/24/2009 12:32 pm
We just got back on here in Israel.
Panga
02/24/2009 12:34 pm
Ok, it seems its working now in France.
Panga
02/24/2009 12:42 pm
Back in France too.
Lully
08/30/2009 09:16 am
why can not I access my gmail account, it shows as below:The server encountered a temporary error and could not complete your request. Please try again in 30 seconds.
Peggy
09/01/2009 08:48 pm
myt gmail is not available, Encountered error 502 Server encountered a temporary error and could not complete your request. Try again in 30 seconds.
pogurschi cornel
09/01/2009 09:10 pm
502 error help gmail no work for Cornel Romania
Max
09/01/2009 09:15 pm
"The server encountered a temporary error and could not complete your request." when trying to log on gmail in Iceland now
Daniel James
03/30/2010 12:52 pm
30/3/2010 Currently on the comment box in Google Blogger "Server Error The server encountered a temporary error and could not complete your request. Please try again in 30 seconds. " <a href="http://webexploits.blogspot.com" rel="nofollow">Webexploits - Helping Expose Web Exploits and Vulnerabilities</A>
Vijay
05/11/2010 04:54 am
first time i ever seen, gmail down, getting error as "The server encountered a temporary error and could not complete your request."