If you're ready for the big leagues of plane spotting, then the place to do with a cup of hot cocoa in hand is just outside the fences a Germany's Hamburg International Airport, at a little food stand called "Coffee To Fly." This shop, which also will happily sell you little sandwiches, muffins, beer and even a 2 Euro glass of Glühwein (a hot, mulled wine), occupies prime plane spotting property on a hill known as the "Fotografenbrücke," or "photograph bridge." From here, Hamburg's runways are laid out in front of you.
If, on the day you go spotting, there's a some exotic aircraft expected, like perhaps a giant Antonov cargo plane or a surprise visit from an A380, you'll be elbow-to-elbow with photographers for whom this a true passion. Read a great story about these guys here.
This is a really long video, but it gives a good idea of what there is to see
The Coffee to Fly knows that the people they're serving are out here in good and bad weather, so long as the planes are flying. Thus, you'll find they're open from 9am to 10pm, 365 days a year. To reach them, you will have to have a car or taxi drop you off where the 433/Zeppelinstrasse takes a strong inward curve alongside the airport's boundaries. The cafe is officially at Holtkoppel 100, so it could be a could idea to Google Map it beforehand (or just check out the one we've already done for you, above).