Do I need an antivirus for my Cruz?
Do you really need an AV for Android? Rather than taking the risk by saying, "No", we instead will say, "Yes, but not likely". When it comes to malware, the "Better safe than sorry" axiom comes to mind.
Every popular Operating System, including Android, will be targetted by virus makers. There currently are very few such Android threats, by comparison to those that threaten Windows. The likelihood of your Cruz system falling victim to one of these threats is rather low, but not non-existent.
AegisLabs (a Lionic company) has developed Egis Mobile, another AV app for Android. Their security blog has an interesting article comparing the testing of their product with eight other AV apps for Android. These apps are largely available via the Android Marketplace.