This week I "got around to it". That thing I knew I should do for so long, but never actually wanted to do. Well this week the itch could not be ignored. Finally I scratched. And now I share with you...
UpAPI
I thought of calling it "Yet Still One More File Helper Module," but decided shorter was better. Because shorter is what this module will do for you, if you need to add file uploads to your module, that is. Your code will be shorter and your time spent will be shorter. At least that's the goal, and you can help by playing with this new module and giving some feedback.
How it Works
upfield.module introduces a form element called appropriately enough 'upfield'. It looks similar to what other modules present, and hopefully works as well or better. I took special care to handle node previews, so hopefully the preview shows what the node will actually look like after you submit the files. While you can use upfield.module independently of upapi.module, I doubt anyone will.
upapi.module handles the "bookkeeping" of file uploads. It saves the file to the right place, and keeps a record in the database. Provides functions to access the files and hooks to be notified of various events (new file, deleted file, etc...). The idea is to handle the basics so developers can concentrate on the specialty of their module.
Right now the best documentation is upapi_example.module, which when enabled adds some file fields to Story nodes. So to demo, simply download UpAPI, enable the modules on Drupal 5.x, and create a Story.
Please take a look at UpAPI and let me know what you think.

Comments
Thought for sure this group
Thought for sure this group would be interested in this module. How wrong I was!
Everyone busy with Drupal 6 or something?
:)
hopefully this will be a
hopefully this will be a drupal 5 only module. uploads got a lot better in 6, if http://drupal.org/node/142995 ever gets committed the other half of this will be taken care of.
Ahhh.... Thanks for pointing
Ahhh.... Thanks for pointing that issue out. I just subscribed to it.
UpAPI has features beyond what's in that patch, which some developers may still be interested in. I'm sure glad some file improvements will make it into 6.