1) Build your own recording mechanism which inserts records from sysprocesses or one of several DMVs on a scheduled basis and do analysis on that table over time.

2) Set up a profile run to log profiler information to disk on a schedule (watch out for overhead on busy systems). Import disk file to table on (different server?) and analyze.

3) Purchase one of numerous 3rd party packages which track resource utilization.

4) Built in reports as someone else suggested.