Invisible text frowned upon by Google? Even get you banned?

I would like to use a few sentences of invisible text at the bottom of my page. This text would be the same color as the background, so it would be invisible.

I heard Google may ban you if you do this with keywords, but I would be using the same text content that's embedded in my flash content. I would like to do this because Google doesn't read my flash text.

Anyone know if Google looks at this as no-no? Will they ban me?

Thanks in advance for anyone's help.

I would strongly recommend not doing that. Google will most likely penalize your website if you do any sorts of invisible text like that.

My suggestion to you would be to either scrap all of the Flash and only use it sparingly, or create two versions of your website and provide a link to your non-flash version of your website for visitors who cannot run Flash (such as iPhone users). That will allow all of your audience to see your website, and will also be beneficial for Google to have access to.

Thanks. Do you know of a way for my homepage to automatically detect whether the person going to my site is a PC, mobile device, or search engine, and automatically redirect them to different pages accordingly?

You can detect what sort of browser someone is using and if its a mobile device or not, and then serve different content based on that. I would, however, not serve any different content to search engines as that is considered "cloaking", and it is just as bad as invisible text and you will get penalized for it.

To detect what sort of browser someone is using you would write a script that looks at the User Agent in the request to your website. You could either do that on the client side using JavaScript, or you could do it on the server side using something like PHP.