We had one last night in Lisbon on New Year's Eve before flying home. I booked the Hotel Jeronimos online, impressed by the favorable rates even during the holidays. The hotel had recently undergone a complete remodel. All furniture and bathrooms were top notch. There's a cute little bar with very friendly service & reasonable snacks. The rate included an excellent buffet breakfast, which had Pasteis de Belem, the famous & delicious custard tarts from the cafe around the corner! Though it's right near many sights, including Jeronimo Monastery, it's a quick bus ride to the center.
I would book here again in a heartbeat.