Self-deprecating:
* "And that's all I have to say. Unless anyone has any questions, but please be gentle, I'm still learning."
* "So, in conclusion, I'm basically a genius. But don't tell my mom, she's already worried about my future."
* "Thank you all for listening. I'm going to go eat now, because I'm pretty sure I just burned 100 calories talking."
Unexpected:
* "Thank you for your time. Now, if you'll excuse me, I have to go find a real expert on this topic."
* "And that's all I have for you today. But I'm happy to answer any questions, especially the ones about why my tie is crooked."
* "So, that's my two cents. Actually, make that three cents, I found a lucky penny on the way here."
Playful:
* "I'm not sure if you learned anything today, but at least you didn't have to listen to me talk for another hour."
* "I know you're all thinking, 'Finally, this is over!' And you know what? I'm thinking the same thing."
* "Well, I hope you enjoyed my speech. I certainly enjoyed writing it, even if it was just to procrastinate on my real work."
Remember to tailor the ending to your audience and the overall tone of your speech. A funny ending can be a great way to leave a lasting impression!