One thing that annoys me about most mainstream science fiction is how unoriginal the alien species are. In the first category, you have what are basically humans, just with some minor feature to distinguish them. Humans with pointy ears, humans with bumpy foreheads, humans with fangs, different colored skin, fur, tails, etc. How boring!
Then you have the second category, which is slightly more creative, but still getting overdone. That's animals from Earth with humanoid features. Lizards, dogs, cats, birds, etc. that walk on two legs and have opposable thumbs. I've seen enough of those to last a lifetime.
It can somewhat be excused in older live-action series like Star Trek TOS since they had a limited budge and CGI wasn't invented yet, but when it comes to mediums like drawing/animation or prose, you can do whatever you want, but so many people stick to the uncreative humanoids.
This is why I love the Shivans so much. They are so unique looking, it's hard to think of any other alien that looks like them:
Some other designs I like include the Shadows from Babylon 5:
Elder Things from H.P. Lovecraft:
(He came up with this almost 100 years ago!)
Mycon from Star Control:
What are some of your favorite aliens that truly look alien
, and what are some good tips for designing them?