This is rather belated; I seem to have trouble summarising long events. tea_cantata posted about the trip earlier and I'll assume you've already read what she wrote.
Sledge and I settled on leaving Cambridge at 11:30 the next day to catch the ferry departing at 14:45. I had to take the car in for its "MoT" test, having put it off almost to the last minute, and around 18:00 I realised the garage had closed without calling to let me know it was ready.
Thankfully the car was ready early on Friday morning and I was able to collect it and get some fuel by around 11:10. Our additional passenger, tbm, arrived at our house by bus shortly afterwards, and Sledge arrived with passengers shortly after 11:30. The journey was fairly long - about 230 miles by road and 2 hours plus waiting time on the ferry - but uneventful. This was my first time trying to drive "in convoy" and my first time driving on the right, but I coped reasonably well, I think.
Most of the FOSDEM attendees at the youth hostel had a round of drinks there, then left for the Roy d'Espagne in two groups a few minutes apart; I was among the laggards and, lacking a map, I attempted to lead the way to the Grand Place based on what I remembered from my previous weekend trip. This was surprisingly successful; it helped that I had stayed nearby on that trip.
The Roy was terribly crowded; not so much as to make me uncomfortable, but enough to make it difficult to get served. I shortly joined a group going elsewhere for dinner, consisting mostly of Debian-UK people, and we ended up in the Leon restaurant not far off the Grand Place. I dithered over the menu but eventually decided to take a risk and ordered a dish marked with a Belgian flag, Anguille (eel) aux verts. This turned out to be quite tasty; the "verts" consisted of an oil and herb sauce not wholly unlike pesto, and some cress on the side. I'm not sure whether the flag indicated this as a particularly Belgian dish or that it would come with a miniature flag and flagpole stuck in it (which it did).
Back at the Roy, greeted many people that I had met previously at Debconf and other events, talked to some - but fewer than I would have liked - and had a a few beers. All too soon it was 1a.m. and time to walk back to the hostel.
I dragged myself out of bed on Saturday morning, and, finding our wash-bag entirely absent of soap, shower gel or shaving cream, had to make do with a minimal wash in the communal toilets and letting my bristles grow. At breakfast, to the digust of most of those sharing the table, tea_cantata got a bowl of cornflakes with what appeared to be mayonnaise, though it was actually yogurt. Shortly after 9, Sledge and I drove over to the FOSDEM venue, the UBL. I think I would rather have taken public transport, but the daily parking charges by the hostel would have been €30.
I found the Debian stand was always well-staffed, so I spent most of the day going to various talks. I'll post the details in a later entry.