9. Listen to your music online. Sure, with sites like Pandora, you can give yourself a customized radio experience with music you like. But how about just playing the music you already have? Imagine taking your iTunes library and storing it online, so you can listen to it on any computer with an Internet connection. That’s Lala. You can upload all your songs to it, and you can buy new songs for 10 cents a piece. Oh, and in case you were curious, Lala is now owned by Apple, so I think calling Lala an online iTunes is a very appropriate analogy.

10. Create your own site with email, calendar, and more. If you’re an entrepreneur with a dream to start your own site and make your own corporate email address and intranet, you may want to check out Google Apps. For free (or for a yearly fee, if you’re a decent-sized business), you can hook up every user on your website with email, calendar, docs, and sites. Hint: If you want a cheap, fast, and easy way to make your own website and have your own custom email@address.com, then try these steps. Step 1: Buy a domain name from someone (GoDaddy charges about $9 a year to register a domain name). Step 2: Hook up Google Apps to it. Step 3: Enjoy. If your site has less than 50 users, then all you need is the free edition of Google Apps, and you just landed yourself a custom website with all the bells and whistles for just $9 a year (the price of the domain name).

11. Make custom t-shirts, mugs, and other clothes and accessories. Want a t-shirt with your picture on it? Want to create a custom hat, tie, postcard, skateboard, keychain, shoe, or almost anything else you can think of? Try sites like Zazzle or CafePress. All you need is a picture and some money, and you’re on your way to having stuff customized the way you like it. By the way, if you have a SmugMug account, you can create custom products from pictures taken directly from your photo gallery.

Blurb makes it easy to make your own book.

12. Publish your own book. Maybe a blog just isn’t enough; maybe you want to get your work published. Or, maybe you just want to create a photo book or record your life’s adventures in a coffee-table-friendly format. Try Lulu or Blurb. Use their software to customize your book, specify the type of book you want, and then either order it or start selling it! If you want a few more options, Mashable has a good article on how to publish your own book.

Looking for some cool utilities? Here are some you may not know about.

13. Get a free phone number to unite all your phone lines. If you have a cellphone, work phone, and home phone, or if you simply want a phone number that lets you block numbers and send people straight to voicemail whenever you want, then try Google Voice. Google can also transcribe your voicemails for you (so you can read your voicemails rather than listen to them), and you can make international calls for a low fee.

14. Convert [something] to [something]. Ever wanted to get an mp3 of a YouTube video because you liked the song that was playing in the background? There are plenty of sites that let you do that. For a more general solution, check out YouConvertIt. Not only does it do YouTube to mp3, but it also does mp3 to aac, doc to txt, and almost any other format conversion that makes sense.

15. Create drawings and save them as SVG, PNG, or PDF. Did you know that you can use Google Docs to make simple vector graphics? All you need is a Google account. Create a new document, and then select “Insert > Drawing.” Play around with the graphics to your heart’s content, and when you’re done, select “Edit > Download as” and pick which format you want. It’s no Photoshop, but it’ll meet your most basic needs. If you actually are looking for something that rivals the power of Photoshop, try out Aviary’s tools such as Phoenix and Raven. Then again, even these days, Photoshop is available online and free (albeit not as full-featured as its desktop behemoth).

16. Update all your social media accounts at once. When you have a dozen or so social media accounts, from Facebook to Twitter, updating them all is a chore. If you want to stay active in all your social media networks and even synchronize a few updates, then consider Ping.fm. With Ping.fm, you can send a status update to multiple accounts at once. You can even send updates to your blog and write full blog posts! I used Ping.fm extensively for a while, but ever since I got my Motorola Cliq, I’ve been using Motorola’s built-in alternative for synchronizing updates: MOTOBLUR.