We stayed here as a couple in November 2011, luckily flying out the day the recent riots turned ugly. The hotel was initially hard to find, luckily the driver had eagle eyes and deposited us in front of a rather grimy looking office block with a sign for the hotel on the inside of the entrance. Going up to the top floor in the small rickety lift you step out into the clean but simple tiled floor hotel. The rooms are clean, no frills, bathrooms small, no shower screen so floor gets wet but like others have mentioned this is common around this part of the world. Bed was firm but adequate, breakfast adequate, not exciting but for the price it was ok.
The French owner is helpful, she warned us to stay away from the square as a result of advance warning of the demonstration so we thought it was a good day to take a day trip to Alexandria. We chose to organize our own sightseeing, preferring to do things independently, and we found this was a much cheaper option than the ones offered by the hotel. Wifi was available though hit and miss, with you needing to sit in a corner near the officecat times to get it to work. The owner was helpful with a map and with telling us about some local eateries. The hotel was in a good location just to wander around, list of non touristy pockets and streets to enjoy soaking up everyday Egyptian life.
One downside was the smell of smoke throughout the hotel, not bad in the rooms luckily, but in the lobby it was pretty strong as a result of the owners and some guests smoking there, not great for the non smokers.

The Osiris is not a large hotel - no more than a dozen rooms on the top floor of an office building. (If it wasn't for a photo of the entrance here on TripAdvisor we'd never have found it.)

The rooms are clean, of a reasonable size and the whole atmosphere is peaceful and quite soothing - especially after a day's walking around central Cairo.

We had a balcony room, which in hindsight, wasn't really necessary - we didn't use the balcony at all. Breakfast each morning was a simple but filling affair - toast, fruit, yoghurt, eggs and tea or coffee. Certainly enough to get you through to lunch time.

The free Wi-Fi was also a bonus, as it allowed us to keep in touch with family and keep an eye on the news reports a to what was happening around Egypt at the time.

We stayed here for a few days at the start and end of our Egypt trip. The Hotel is on the top floor and has some interesting views of Cairo from the roof top terrace. The hotel, while certainly not flash is nice and clean and overall a very pleasant place to stay, the staff are friendly and helpful. The ride to the 12th floor is somewhat of an experience in the elevator, you never quite know if you will make it or not.

The tours the hotel organised on our behalf were great, the driver and guide were excellent and we enjoyed the trips we did, probably a little over priced so you could do better if you haggled or shopped around, as was their airport shuttle service. Expect to be shuttled into various shops to buy various wares while on the tour, but there is no compulsion to buy.

Things to watch out for – the overpriced Nile cruise, which is a tourist trap, meal wasn’t anything special and Raed, our ‘guide’ stayed with us the whole evening including eating with us, a little odd, and despite our attempts to escape we were tracked down! In fact apart from collecting some sort of cut in our payment I’m not sure why he was even needed.

The hotel is walking distance to the square and museum, which is great, has wifi although coverage could be better. Breakfast is served on a nice balcony overlooking the city. A clean and pleasant oasis in a chaotic and noisy city.

The hotel is at the top of a somewhat dilapidated building near Tahrir Square. I thankfully flew out just before the riots started early in 2011 (but to be honest, I never saw any signs of them coming).
The views from the rooftop terrace are great and it's nice to have breakfast there. The hotel offers basic, brightly painted rooms with ensuite bathrooms. There are no luxuries, but it's clean and the price is good.
Trips outside Cairo can be arranged by the owners. I would particularly recommend a private tour to the lesser-known pyramids, which compared to those in Giza are far less touristy. I left early in the morning, arrived at a pyramid, walked around it and found myself all alone, the desert on one side and the pyramid on the other. It was a magical experience. If you take the tour, agree on the price before you make the booking.
The location means that the Egyptian Museum is at walking distance and, if you don't mind a longer walk, so are a number of Islamic sights. There are a number of affordable restaurants in the area.
All in all, a good midrange option.