For multiplication, Timez Attack from bigbrainz.com was a huge hit here.
I have never tested dd on maths facts. She started by reading the facts and doing a short drill immediately. Now she just does a drill each day (50 questions, usually). I check, and we might discuss any mistakes, but there is no pressure. I think mastering the maths facts is hugely important, but I also think it takes time and repetition, and that pressure is counter-productive.
Oh, I just remembered - we did a few fun things right at the beginning. I numbered balls 0-9, and would throw them at (umm, sorry, to) her and she would have to add to the assigned number. If we were doing the 3+ and she caught a 9 she would shout out 12, etc. We also bought a 10 sided dice, and did a similar thing with that - she had to add the face number to whatever number we were dealing with that day. We did the same with cards, using 1-9.