Digital photo frames are a great way to show off your photo collection, but many of them have a much lower display resolution than your images, so you end up wasting space storing pixels that are never actually displayed. FotoFrame resizes your pictures before you copy them over, allowing you to store more images without splurging for a higher-capacity SD card.
While image-editing tools such as Lifehacker favourite IrfanView include bulk-resizing tools, FotoFrame makes the process extremely straightforward. Tell it where your photos are, where you want to copy the resized versions and the resolution of your frame, and it does the job automatically. You can tweak settings such as image types included and the quality of the resulting JPG files, but for most uses the defaults will be just fine.
FotoFrame is a free download for Windows.