I love a good free web service that is actually useful. There are a lot of times that I need to send people files that are just too big for email. I have used several online services in the past (with varying results) such as DropSend, YouSendIt and senduit but none of them quite compare to Drop.io.

Drop.io calls itself “simple private exchange.” Basically it is an easy way to share files online. On the surface it’s as simple as choosing a name for your “drop” (or using the random default name provided for you) and then choosing a file to upload to your “drop.” Then all you have to do is email anyone in the world the URL to your newly created “drop” and they have access to whatever file(s) you uploaded.

However, Drop.io goes beyond simple file uploading. First of all, it allows you to configure some basic settings while creating your drop. If you want everything in your drop to stay private and you want more security than just the randomness of your chosen URL then you can set a password for your drop. With a password set, anyone who wants to view your drop must know the password to gain access. You can also select how long your drop should be available to the world. You can even select what you want other to be able to do with the contents of your drop. People can either view files, view and add files, or view, add and delete files.

But it doesn’t stop there. Once your drop has been created you are asked if you want to create an admin password. You do. This password allows you to “administrate” your drop after it has been created. In the “admin” panel you can do things like destroy the drop, change the URL, extend the life, change passwords, change the logo, or upgrade to a “premium drop” (more on that later). It also tells you how many times your drop has been viewed.

But I know what you are thinking. You are wondering, “Whatever can I add to my drop? Is it only for file uploads?” Well, no it’s not. You can add any kind of file, links, or even text (notes) to your drop. Drop.io will even help make your files/content more web-friendly by automatically create thumbnails for images, flash versions of videos, etc. It also allows you to view your drop in any of three different ways. The “Blog” view is reverse chronological order just like a blog would be (newest on top). This means you can use your drop as a simple tumblelog (people can even subscribe to your drop via RSS). You can also view your content by media type using the “Media” view. This separates your pictures from your documents, etc. Finally you have an “Interactive” view that is perfect for displaying photos as a photo gallery.

Drop.io even allows you several different ways to add content to your drop. You can always login as the administrator and add content via the drop itself. But you can also email or MMS files to your drop, you can call a special number/extension and leave a voicemail for your drop (which gets converted to an audio file), you can use the drop’s “conference call” number to talk to a group of people, or even fax documents to your drop using a special cover sheet.

Drop.io graciously gives out 100MB drops for free, but once you start adding things to your drop you may find yourself running out of space. No problem. For $10 you can upgrade your drop to a “premium” drop and get 1GB of space for one year. You can even make your drop’s URL shorter with a “premium” drop.

So, whether you are looking for a quick and easy way to get that big file to a client or you need a place for your friends to share their photos from last weekends adventures, I am sure you can find a great use for Drop.io.