How can budget not be important. Also, what size do you want. Mid tower to full tower.
Some of my favorite cases
Corsair 600T : $150 Out at end of month, great midtower case, ton of room
Corsair 800D: $275 Huge case, tons of features, very nice looking,
Antec 900/902: $115 3/4 tower, great airflow, tons of gamers have this case
Antec 300: $55. Nothing elaborate, mid tower, functional
Antec Sonata III 500: $145. Comes with 500W power supply, nearly silent, great case ( i have 2 of the Sonata II's).
HAF -X: $200. Full tower case by coolermaster. People love 'em, nice features. Industrial look which I don't care for.