You will be syncing via a "cloud" service rather than by account. You can use the same or a unique name for accounts and passwords.
Saving your files to DropBox is very easy to keep files in sycn across multiple devices. Even if you have an older computer, DropBox will work even if they are too old for iCloud. DropBox is free up to 2GB, but you can pay a monthly fee or yearly fee to get 100GB.
Apple's iCloud can sync items like your Safari bookmarks, mail, contacts, calendars and photos.
You can also transfer files via external drive or file sharing when you get home.