It doesn't just do one-offs. You can scan multiple pages and compile them into a single PDF file with one click. How to Use It (The 3-Step Workflow)
It’s a portable app. You can run it straight from a thumb drive without messing with your Windows registry. WinScan2PDF
Open the app and click "Select Source" to find your scanner. Scan: Hit "Scan" to pull the image from your device. It doesn't just do one-offs