This is the bike I just got and I love it. I ride it about 10 miles a day in the city and its great for all kinds of riding. Its a Big Ripper (a 29inch version of the famous 1980s Pk Ripper) You can find it for $450-$500.
If you want an all around fun bike that is easy to ride, goes fast, is light and involves very little maintenance this is the one to go with. And remember its a 29" bike... not a 20 or 24 inch BMX bike.