Node Clone http://drupal.org/project/node_clone works quite well for creating clones of nodes and is included in the Barracuda/Octopus Drupal distributions so has quite a few sites using it (23k reported on the project page).

There are a few outstanding issues regarding incomplete or incorrect cloning of nodes that would cause problems for many production sites so Node Repeat might find it useful to leverage the cloning functions in Node Clone and focus solely on the sequencing code.

for examples of the kinds of issues i'm talking about see:
#1086842: Author Field Not Properly Updated Upon Node Creation, #1127516: General Compatibility with other node modules, #1133646: Wrong time when creating repeat addition, #1088410: Generate each date as a single node not working, #790878: All but first node in repeat sequence is Anonymous, #1190616: token support