Whilst I know it's not what people USUALLY say on the forum...
I've done it before and it was cool !
When people are attracted to each other, all the other co-workers around notice anyway and usually think that something is going on MONTHS before you actually get together...and then when you do and you tell them, they are all "oh wow, that's so cute".
(and we split up because I left the country - no other reason!...)
Do it!