Dropbox is a wonderful option for people who need to mail out very large files. If you are constantly emailing files to yourself, using USB drives to transfer files, or if you need somewhere to share pictures, you can use this program to do so. There is a free version that allows you to use 2 GB of storage. The pro version costs around $10/month and allows you to use 50 GB of storage. The pro 100 version costs around $20/month and allows you to use 100 GB of storage. You can try the pro versions for 14 days free.