I needed a simple scanner app for work. I found a good one: NAPS; except the PDF output was bloated, and the app itself hasn't been updated in a while. So I tried fixing it to suit my needs. I will probably have to make further updates as needed, else maybe the original author can integrate the changes.
Tested with the TWAIN driver on a Brother ADS-2000
Working copy + source code
Updated version from January 2013