Here an issue one for those new-fangled 
etiquette guides (you know, the ones that exist to tell your parents that leaving 
caps lock on in an email = shouting).
What is the 
etiquette surrounding the office kitchen’s 
microwave?More specifically, if I am waiting to use it, and the 
timer has long since sounded on the 
unattended lunch currently inhabiting the microwave, how 
long do I have to wait before I can 
pull it out and use the microwave myself?
I’ve waited quite some time in the past, 
paranoid that touching someone else’s lunch is invasion of personal space by 
proxy.
This is clearly 
too long to wait, and whilst it keeps me away from my phone and email for a 
blissful extra 5 minutes, I can only read the 4-year old notices on the 
notice board so many times.
By 
contrast, on another occasion, I’ve walked back in to the 
kitchen just as the timer was sounding on my lunch, only to find someone else 
pulling it out so they could get their left over tuna mornay in as quickly as 
possible.
To me, this is 
too hasty – what if I needed to
 stir my lunch and heat it for a further 
2 minutes?Modern living is so perplexing.
EDIT: I just wanted to note that I, like a couple of commenters, am of the view one should stick around and wait 
with one's meal.
However, I have 
perfected the timing of my reheating such that I can make a quick 'comfort stop' in the time it takes to reheat my 
lunch. So I feel 
ok in leaving it to cook unattended.  I am a 
responsible microwave user.
Furthermore, more often than not, waiting with my food while it heats up will involve 
banal small talk with whoever else is 
waiting to use the microwave and I have a very limited 
tolerance for meaningless niceties or talk about the weather. Setting my lunch to heat and walking off to do something else is often more of a 
survival mechanism than anything else.
But what I am definitely 
not a fan of is the 'queuing by proxy' some people undertake by leaving their 
tupperware in a little queue next to the microwave and then 
lobbing off back to their desk.
Tell you what, if the microwave becomes free and no one is around to 'claim' their place in the queue, I'm 
not hanging around waiting for you to return.