You dont want to manually use a software like FastStone Photo Resizer and are looking for a better option which can resize your JPEG Photos? Then here is one called as DropResize which is a very small utility performing a awesome job. The moment you run this 55kb windows utility it starts running and does not install any software on your PC. You will be shown with DropResize Configuration settings which would mean that you need set a folder on your Computer which it monitors regularly.
Its recommended to keep the quality at 100% and change the size of the Image Height & Width and basically this can be a really useful tool for bloggers because you can quickly create thumbnails for the photos you download by just dragging and dropping a copy of photo in the folder you had set up previously.