In today’s digital world, our entire life — both work and home — are tied to computers. Hard disks are unpredictable and are prone to failures leading to data loss. Research shows that every year 43% of computer users lose valuable data. The best way to hedge your data storage risk is to store critical data on the cloud. This things also make your data available at the time you want it. It keeps your data synced over you pc, online, smartphones, tablets, etc.

Some of the best services available-

Dropbox

Dropbox lets you bring all your photos, docs, and videos anywhere.

Dropbox is a free service that lets you bring all your photos, docs, and videos anywhere. After you install Dropbox on your computer, any file you save to your Dropbox will automatically save to all your computers, your Android device, and even the Dropbox website! With the Dropbox app, you can take everything that matters to you on the go.

Read your docs or flip through your albums when you're out and about. Save photos or videos to your Dropbox and share them with friends in just a couple taps. Even if you accidentally leave your Android in a taxi, your stuff is always safe on Dropbox.

Features:
• Always have your stuff with you, no matter where you are.
• Save photos and videos to your Dropbox.
• Share your photos and docs with family and friends.
• Save email attachments straight to your Dropbox.
• Easily edit docs in your Dropbox.

Dropbox app is available for Android, iPhone, iPad, BlackBerry, Windows, mac & Linux.

It gives you 2GB free and later you can buy some more space. It also some offers which can get you more space. Link.

I think that it’s best as you can get share your files in the web. As you upload a file, it gives you a link for that file !

Windows Live SkyDrive

Despite having a name that is quite a mouthful, Windows Live Skydrive is one of the most popular and extremely useful cloud based service from Microsoft. Windows Live Skydrive offers a hefty 25 GB free storage space to all users.

There is absolutely no need to install and configure a desktop client. All you have to do is log into the Windows Live Skydrive account wit your Live ID and you can just drag & drop files into the folders. In addition to having password protected private folders, you can create new folders, make it public and share the files with friends, family or coworkers.

Each folder has a unique weblink which you can mail to anyone you want and the files can accessed from any web connected device like a PC or a smartphone.

SkyDrive app is available for Windows Phone, iPhone & iPad, & Windows. For Android and other phones, you can still use SkyDrive. Just open your phone’s web browser and go to SkyDrive.com. You might need to sign in with your Windows Live ID. Find the file or photo you’d like to view, and tap it.

Google Drive

Google Drive lets you store and access your files anywhere -- on the web, on your hard drive, or on the go. Here’s how it works:

Go to Google Drive on the web at drive.google.com.
Install Google Drive on your computer or mobile device.
Throw your files in Google Drive. It’s right there on your device.

Now your files go everywhere you do. Change a file on the web, on your computer, or on your mobile device and it updates on every device where you’ve installed Google Drive. Share, collaborate, or work alone: your files, your choice.

Store the first 5 GB of your stuff for free.

When your Google Drive grows, get another 25 GB of space (or more!) starting at $2.49 per month.

Access everything in your Google Drive from all your devices.

Your files are always waiting for you at drive.google.com, but you can also get them straight from your computer, smartphone, and tablet. Install Google Drive on multiple devices and Google Drive makes sure they’re all the same. You can even get to your files after you go offline.

Keep files synced. Just connect to the web – it's pretty much automatic.

Any time your device has Internet access, it checks in with Google Drive. That ensures your files, folders, and Google Docs are always up to date. Change something on one device and it changes everywhere.

Stop emailing attachments. Start sharing.

Google Drive lets you choose exactly who – friends, family, colleagues – gets your files. You don’t need email attachments anymore. Just share your file, folder, or Google Doc from any device.

Keep collaborating!

Do you collaborate with others in Google Docs? Google Drive lets you continue to create, access, and collaborate in a version-free world.

Google Drive app is available for Android & Windows.

Note : Google Docs and Google Drive have been integrated!

Some more..

For individual files, some great options are-

For music-

SoundCloud
Kiwi6 - It can help you by giving you embedding codes and a direct link to your .mp3 files

For pictures-

Picasa - Picasa is an image organizer and image viewer for organizing and editing digital photos, saving images over cloud, plus an integrated photo-sharing website, owned by Google
PicturePush - Useful for uploading High Quality images, as it doesn’t distorts the image after been uploaded
DropMocks – Easiest! In it, the thing you need to do is, drag your image files onto this site, and they will do the rest. (Chrome Web Store Link)

For Swf files – swfCabin

For videos-

YouTube – We all are aware of it.
Vimeo – In it you can upload a video with 10+ minutes (unexpectedly, which the youtube don’t gives) in a condition 5GB/Week

For Miscellaneous

GE.TT – In my opinion “The Best Cloud Storing App”. You can drag your files to this site and you will instantly get the link which you can share while its been uploading! (Chrome Web Store Link)
box – It’s only best for sharing a group of file over the web.