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4) Travel Blogs
5) Tech Blogs - Mobile, Tablet, OS, Drones, TV, Camera, Smart watch etc are some of the hottest niches right now
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The best advice, thank you very much!Pro tip: Look out for ideas on DP, Flippa, WJ etc in their site sales section B-)
There are millions and millions of them, and they are not different. It should be really great and new type of them. In other cases it's not the best option...