[UCANSEE2]

Can you use it on your computer?

You don't need it on your computer. Your computer can access the same sites the ROKU does.

You CAN also purchase a device that connects your TV to your computer.

The difference between the two setups (ROKU vs. PC linked TV) is that ROKU provides a definitive list of VIDEO sites, whereas on a PC you have to find (or know about) them yourself.

ANOTHER OPTION. If you have an XBOX ONE, it performs the same task that a ROKU box does. My son browses the Internet and watches movies all from his XBOX ONE.

[UCANSEE2]

Here, for example, as some MOVIE streaming sites you can access from your PC. Right now, for FREE.

http://www.alluc.com/

http://www.shush.se/

http://www.ovguide.com/movies

http://www.freefullmovies.net/

[GeronL]

Another variety would be programming a Raspberry Pi ($35) with XMBC and turning it into an internet cable box thing.

There are videos at Youtube on doing that.