Hilton are this week running a “flash sale”. Up until 11th October 2015 you can get some reasonably priced rooms around the world.
Taking a quick look at the hotels in the list, most places are on offer at around 20-33% discount. On a single room and single night basis you might not feel the savings, but on multi-room or multi-night I'm sure that discount can be pretty substantial.
Despite the conspicuous text of the banner above, if you're looking for some cheap stays for mattress running, the lowest available rates I see are £28-32 per night in Turkey, and £32-35 in Poland. Don't forget if you are a Hilton Hhonors Gold member, you can get free breakfast and in most cases executive lounge access.
If you're not a Gold already, then there are several fast track methods available. Here is one where you need to complete 4 stays in 90 days.