This is one of the coolest apps I have ever heard of. You take a basic image, say of a Street Sign, upload it with Legoizer and it will break it up into a brick-like model. That's not all! You will also be given a shopping list of all the Lego bricks required to make your image model. The fact that you are given a list makes it so much easier to create the image model of your choice. Think of the funny things you can recreate with Legoizer and your Lego blocks. It's worth noting that due to the popularity of Legoizer, the site is lagging but if it doesn't work for you first time then keep trying.
To make your image model you will need lots of Lego, but not any of the fancy bits that come in the themed sets. I think Legoizer just highlights the versatility of Lego and why it's still popular today. There's not much that cannot be build out of those multicoloured blocks.
Sets like these Lego Classic ones have a selection of Lego bricks that can be used to make anything really. Check them out: Lego Classic Creative Supplement Bright* just £14.49, Lego Classics Creative Bricks* just £11.97 and Lego Classic Large Creative Brick Box* just £31.97 delivered.
Image credit: petapixel.com