SoftCollection Impulse Counter supports up to 12 counters, counting impulses via parallel port.
All you need is to connect a button via 500 Ohm resistor between Parallel Port's ground (pins 18-25) and pin, whose number appears above the counter.
You may set a name for a desired counter.
The counters will be able to process 20 counts per second and will programmatically prevent contact bounce consequences.
