...with a coworker, how can i do that?

Try netmeetinghttp://www.microsoft.com/windows/netmeeting/It allows you to share your entire view or individual windows. You can also let someone control your computer or individual windows.

There are a number of ways you can do this. The best I feel is gotomeeting.com. You can share everything, it's 20/mo. You can also download Skype then festooninc.com which will allow you to share your desktop although it's not as clean. There is also a company called glance.net is another one.

You could try the tool called Tight VNC. It's open source en you find it via the added link.

sourceforge.net

I recommend Microsoft NetMeeting. Most computers nowadays already have it installed (as part of Internet Exploder), and it works fairly well.It is, however, a bit tough to locate at times. If you can't find it in the Start Menu, go to Start, Run, and type "conf" into the Open box.After a short setup session, you'll be ready to go. I recommend (for corporate use especially) NOT connecting to any Directory Servers (this means de-select the box that says "Log onto a directory server", and select the option "Do not list my name in the directory".When you've both completed the process above, one of you should go to the Help menu, select "About Windows NetMeeting, and write down the IP address displayed at the bottom of the resulting dialog box.Give the IP address recorded to the other party, have them type it into the box to the left of the phone icon on the main screen, and hit Enter.Once you've established a connection, the party wishing to "share" their desktop with the other person(s) should go to the Tools menu, select "Sharing", make sure "Desktop" is selected (de-select "Share in true color" as this will speed things up considerably), then click the "Share" button.If you want to collaborate on a project, you can experiment with the "Allow Control" button in the same Sharing menu dialog, or play with the whiteboard and chat applications.Another application which will also perform basic remote monitoring/control is VNC. I recommend the TIGHT encoding version which can be obtained from http://www.tightvnc.com. Be warned: you will need to install the server on the machine that you wish to monitor/control, and the client portion on the system you're watching or controlling from.Good luck!

Use Microsoft Netmeeting or a similar piece of software