If this query comes in your mind several times, then my query is- "what you can't do online?"
Well, I've listed bellow things that you can do online easily. I've not only listed them but also tried to discuss them as clearly as I could.
#You can do Online:
1) Blogging
2) Affiliate Marketing
3) Data Entry & Copywriting
4) Setting up an online shop
5) Graphics Design
6) Web design and development
7) Online PTC
8) Selling your service
9) Web Mastering by owning a web site.
and many other things you can do online.