Dynamic NAT configuration on ASA 55XX

Configure using 8.0 ASA

ciscoasa(config)# nat (inside) 1 192.168.2.0 255.255.255.0
ciscoasa(config)# global (outside) 1 10.2.2.1-10.2.2.10 netmask 255.255.255.0

additional note: Running PAT

ciscoasa(config)# nat (inside) 1 0.0.0.0 0.0.0.0
ciscoasa(config)# global (outside) 1 interface

Configure using 8.3 ASA

ciscoasa(config)# object network MyOutsideRangePool

ciscoasa(config-network-object)# range 10.2.2.1 10.2.2.10

ciscoasa(config)# object network MyInsideNetwork

ciscoasa(config-network-object)# subnet 192.168.2.0 255.255.255.0

ciscoasa(config-network-object)# nat (inside,outside) dynamic MyOutsideRangePool  

Additional example of Dynamic NAT of 2 internal networks
Configure using 8.0 ASA
ciscoasa(config)# nat (inside) 1 192.168.2.0 255.255.255.0
ciscoasa(config)# nat (inside) 2 192.168.3.0 255.255.255.0
ciscoasa(config)# global (outside) 1 10.2.2.1-10.2.2.10 netmask 255.255.255.0
ciscoasa(config)# global (outside) 2 10.2.2.11-10.2.2.20 netmask 255.255.255.0

Configure using 8.3 ASA

ciscoasa(config)# object network MyOutsideRangePool_1

ciscoasa(config-network-object)# range 10.2.2.1 10.2.2.10

ciscoasa(config)# object network MyInsideNetwork_1

ciscoasa(config-network-object)# subnet 192.168.2.0 255.255.255.0

ciscoasa(config-network-object)# nat (inside,outside) dynamic MyOutsideRangePool_1 

ciscoasa(config)# object network MyInsideNetwork_2

ciscoasa(config-network-object)# subnet 192.168.3.0 255.255.255.0

ciscoasa(config-network-object)# nat (inside,outside) dynamic MyOutsideRangePool_2 

ciscoasa(config)# object network MyOutsideRangePool_2

ciscoasa(config-network-object)# range 10.2.2.11 10.2.2.20