If you are able and willing to book far ahead, you can get significant reductions on some otherwise expensive cruises. For example, with Viking River Cruises (www.vikingrivercruises.com,) you can receive 2 for one prices on their 2015 voyages in Russia, Europe and China if you book and pay by the end of June. Two for one air fares may also be available.
I'm not one of the people who is willing to book trips far ahead, but if you are you can save a lot of money. I know people like this, who plan travels years in advance, and it seems to work for them.
Cunard (www.cunard.com,) is also offering savings for its 2015 cruises, and even on some of the 2014 Mediterranean sailings. For certain cruises, passengers receive a free balcony upgrade, free gratuities and a free bottle of wine.
In addition, Cunard recently announced that it has installed some new single staterooms on its former flagship, the Queen Elizabeth II. The staterooms are generous in size, most have windows and they are located midship, so I suspect they will be relatively costly. I couldn't find any price information on their Website. I am happy to see that a few cruise lines are starting to cater to single travellers, at least.
If you are a fan of cruising or would like to become one, it is a good idea to work with a travel agent who is a cruise specialist. They can often get better deals than you could on your own.