There is a lot of good logos out there, but many more bad ones. The ones that I do like are like the Vans logo or the Aldi logo.
I enjoy the Aldi logo for it's simplicity and almost this retro vibe it has. The swooping lines that form an A is aesthetically pleasing. And the swooping A could even stand alone and I would still know it's Aldi.
The Vans logo is another piece of branding that I enjoy as much as their shoes. Some so iconic about the simple addition of a horizontal line attached to the V can make it stand out. It also has some representation, like it looks like a skateboard.
Now this is a logo I hate. This is a logo from a local frozen yogurt shop from where I am from in Jefferson City, MO. I really don't like the clip-art looking Y with the tongue, and it doesn't go with everything else. Also, the tiedye is a bit much.