DVDtoMe closed as of early 2006, but we're keeping this review as it was for posterity.
It was established in early 2003 when the DVD rental boom was just heating up. Their site is simple but fairly well-designed, listing a full 18 genres. However, as a smaller company we noticed some surprising gaps among popular recent releases. When queried about how many titles they stocked, they stated they had "24,000 individual discs including series and box sets"--a bit cheeky as individual discs within series and discs of extra are not titles in themselves, but we've heard that the big companies use this tactic as well to inflate their tallies, so we can't hold that against them.
In addition to searches on title, actors, and director, they also allow you to search the synopsis, which is rare in the UK sites. They could definitely use critic/customer ratings and reviews, though.
Although we'd initially heard good things about this small rental company's system and customer service, our own trial in the early 2005 found it sorely lacking, and we knocked it halfway down our table as a result.
Prices: DVDtoMe's free trial period is two weeks at the two-disc level only, and they have very cheap two disc rates--the cheapest in the UK at this level. They offers a 2 disc subscription at £9.99 (the rate most services charge for one disc), and 3 discs at £14.99 (back up to the industry average), and 4 discs at £18.99. Note, if you want to cancel after the free trial you must give notice and return all the DVDs within five working days of the end of your trial period. Like so many DVD rental companies, DVDtoMe appear to be very slow in answering customer emails; especially if you want to cancel after a free trial--you then have to fight to get the charges removed from your credit card--given this hassle, we can't recommend subscribing with this company.
Nice-looking site and very cheap, but customer service is terrible--
Design: 
Rental Basics