yes, you can go to messenger with your nintendo dsi. you can do it by going to the internet on your dsi and go http:/mobile.microsoft.com and just pretend your dsi is a cell phone. next, go to the little link that says "windows live" and it says " hotmail, messenger, spaces" then, you tap on the link that says messenger, then scroll down to the part that asks you for your so called mobile carrier and select the option that says other. tap on select . lastly, hopefully the browser will go back to the home page of the windows mobile page, then tap on the orange access link that says "access windows live messenger from your mobile browser.then, hopefully, the messenger sign in page will then show up. i recommend you to add the messenger sign in page to your favorites so you won't have to go through the entire process yourself. well, good luck with your dsi.