Strange request... This is likely something you would need to figure out yourself, since you'll being giving a presentation on something you are knowledgable in. There are so many sites on the web that headline new technologies. Manufacturer sites usually have list of new and developing products, sometimes free samples and developement kits. Best thing would be to hit the search engines and check what's new in your field of interest, something should catch your attention. After settling on a topic, come back here, post it. Maybe somebody has a similar interest, saw related resources, or has actually been working to develope a project in that area.
After you get started, you might get some help putting together your presentation, circuits for demostration, ect...
Not much total strangers can do to help, we don't know your course work experience, don't what you are required to include in your seminar.