Leburta

You'll need to double check to see if any of the airport hotels have a shuttle service that run in the "overnight" hours. But it hardly seems practical to get a hotel for so short a stay (approximately 5 hours by your calculations). If you can get some rest on your inbound flight, maybe it's not a bad idea, as some others have suggested, to try to stay up in some quiet area until you can check in. Unfortunately, my recollection is that there are not of places to actually sit in the check in areas at CDG -- more once you move into the gate areas.

Christina

There aren't really places to sit in any airport's check-in areas, in my experience. CDG has more than some, they do have a few seats near the windows. There are some coffee shops around that are in the open area, I know there is one in the area in-between 2E and 2F.

Hotels like Sheraton don't rent rooms by the hour, that's a different kind of hotel.

Flightofbumblebee

I am flying in from Casablanca and then on to Krakow. Yes I will possibly nap on the flights but neither flight is long enough to sleep.
I think I will get a hotel. I have sussed out the shuttles and after midnight they are far and few between. Most only 'come by' on an hourly or 2 hourly basis. So it may mean that if I rely on a shuttle I will get to the hotel and literally get back on the shuttle to check in! So, it will need to be a taxi.

I hadn't considered 'priceline' to bid for a hotel so I will suss that out for sure.

Christina - do you know what hours the coffee shop/cafe are open in the check in area? Most airports shops etc close at or before midnight.

kerouac

The Ibis at the RER T1 station wouldn't require a shuttle; it also has hourly rates.

Flightofbumblebee

oooh, thank you Kerouac!!!!!! Will check it out now. Sadly, I don't mind be on the hourly rate just this once! lol