I'd give it away to any greedy relative and former 'friend' who shows up at my doors asking for it.

A small amount (under $50,000), we'd buy a new car for me, my 12 year old 2-door isn't going to cut it when baby #2 comes. We'd put the rest of it away.
A moderate amount ($500,000), we'd still buy the car and put most in savings. The rest we would help out any deserving people we know and have a little fun too like take a vacation. We'd also start a few household projects like building a deck and finishing the basement. We'd also visit far away family more or pay for them to come see us.
A large amount ($2,000,000). I'd get the car, still nothing overly fancy. We'd put a good portion in college saving funds and retirement funds for us. Of course we'd have fun like take vacations. DH may want to consider changing jobs even if it means a pay cut. If we invest the majority of the principal, the interest can make up the difference without a change in lifestyle.
An obscene amount ($10 mil +). OK this is where I would go a bit crazy. First I'd hire a financial planner and lawyer. A lot of the money would be invested. I like the idea of getting paid over time as opposed to a lump sum. DH enjoys working, but this would give us the freedom to pick his job even for less pay. We'd consider buying a new house, not a mega mansion, but a large house with some ground and 2 spare bedrooms so family and friends can be comfortable when they visit. Put away college tuition for our own children (who are very far from college age) and also help out DH's nephews who are college age or very close to it.
No matter how much I would win, ridiculously expensive cars, over the top mansions, or purses and shoes in the thousands of dollars just don't appeal to me and not to many others from the posts I've read. So many lottery winners seem to go crazy with these things. I would want to enjoy the money and celebrate the win by spending a little of it, but also make sure it lasts for the future.