Lacking the vast knowledge of Apple hardware vs. my knowledge of Macintosh stuff, and Google's suckey results for info on this card.
Does anyone know what this card does:
Shamrock computer inc.
1982
-- Disc-Writer Interface --
It has two 20-pin boxed headers (just like Apple II floppy connectors) on it, labeled 0 and 1. One of them has bent pins that could be fixed if I ever have reason to get it working. 
Is it just a 3rd party floppy interface?
I could scan the card if anyone wants to see it.
Sounds like a disk controller but a pic would help. There were a few hunded brands of disk controller not to mention thousands of other cards, Most of the disk contollers were just strait clones of the Disk II card but there were some interesting original designs.
Wayne
It looks like my Apple ][ Disk Interface, however it has some extra chips on it.
I'll scan it right after I finish watching this videotape of The Transformers that I made when I was a kid. (The VCR is sitting on my scanner at the moment, running to my 7500 hehe)
Here's a crappy, dark scan of the card:
http://hotline.kicks-ass.net/discwriter.jpg
It's larger than the original Apple card.
I have similiar cards with the EPROM. I'm guessing that like mine it automatically reconfigures itself for either 13 sector or 16 sector disks, Whichever one is in the drive at startup. Handy if you have some DOS 3.2 disks,
Wayne
I think I'll just stick with the Apple card seeing as I only have one drive. And one disk for that matter. Probably the worst thing ever made for a computer - Facemaker. haha
You may not have cared for them but. . . well, a disk drive was far better than a cassette recorder. (Every Apple II, II+, and IIe has built in support for one of those baby's, right up to and including the 1993 issued Platinum //e, all had the cute little logo for a cassette recorder on the back.) With random access, 140k capacity per side, easy conversion to being two sided ( a hole puch will do the job) and Pro-DOS capable, the floppy disk drives still run well when maintained properly.
Still, I really enjoy using the awesome Compact Flash card interface with the IIe. It's just so darn fast, capable, and compatible with the ancient computers and an OS9 equipped Mac. . .
I was talking about Facemaker, not the drive, dude.