Andromeda's filters, unlike some, are technically useful rather than just for fun. LensDoc fixes lens distortions so that straight lines don't appear to curve or slant inward. Perspective works like Photoshop's Skew, Distort, and Perspective commands, only it's easier and has a more flexible interface. Check it out in Figure 19.12.
Figure 19.12. This filter really puts things into perspective.
And there are more. Velociraptor puts motion trails behind moving objects; the Shadow Filter does the best drop shadows yet. I could go on. Instead, go download some demos from these nice folks and see for yourself. Find them at http://www.andromeda.com/.