Welcome, seone, to ET.com. You can find
info about BluePill here. BluePill's a very good app, I use it myself. Many of the security apps out there are slightly vulnerable to someone who knows what they're doing and wants to get access to your Treo/data. BluePill takes it a step further and can't be circumvented by the hard reset route.
Teal's got a heckuva lot of features. I use it, also. There are a couple threads here in the 700p forum that mention it. Just do a "search this forum" for teal, and you should see those threads.