Slides to Video
I put slides on DVD for 35 cents per slide. The video signal is a lot lower resolution than the slide, so you're sacrificing quite a bit of sharpness for convenience.
Slides to JPEG CD
I can capture slides to 8 megapixel JPEG files for 50 cents per 35mm slide. This is still lower resolution than the film, but it's a lot higher than video resolution. It's a hands-on process, and I check the files and rotate the vertical slide files back to vertical Here's some samples:
I can also capture from medium format slides for 80 cents per slide. It's a similar process, but requires a bit more labor in slide handling.