"Star Wars" Wipes
Here's a collection of some of the "wipe" edits from the very first Star Wars film. Not sure how common the wipe was in the mid-70s, but it seemed a deliberate choice by Lucas to recall the serials, as well perhaps as an homage to Kurosawa who I believe used it occasionally in his films.
It's interesting to see how he and his editors chose to vary the direction and shapes of the wipes to harmonize with events on screen, emphasize certain aspects of setting, character, etc. This screencap, for example, like most of the desert wipes, almost appears as a mirage as one scene blends to another.
This was a "clock" wipe, with the new scene appearing as the wipe swings clockwise around the frame from a central axis. Effective, obviously, for suggesting the passage of time.
Here the Storm Trooper is holding up a circular piece of hardware, while the wipe echoes that shape, starting as a pinpoint and expanding to fill the frame.
One aspect of wipes I like is that you get to see two scenes at once, though unlike split-screen, they're not necessarily meant to be seen simultaneously, so there can be some interesting unintended juxtapositions, even if it's just the difference in textures or lighting. 
Here the transition from indoors to outdoors is handled with a wipe that follows the path of a shadowed character as he crosses from one side of the frame to the other.
