Girl meets aliens, including intelligent purple ball
14699
Late 90's or early 00's graphic novel with a girl and an airship
87947
Employment office encounters an alien masquerading as a human
67028
Identification: a story about an entire spaceship converted to anti-matter
54924
Alien studying human race for mental capacity and ESP
155355
80's TV-show about "digital" alien
124050
Movie where a boy is transported into the future by an alien spaceship
99076
Short story (maybe two in the same collection) about Alien education versus Earth
46628
A story about a whole crew of aliens who visit Earth, befriend a child
5431
Trying to track YA novel - virtual reality simulation aboard an interstellar generation ship
146009
Short story about aliens who want to trade items for information, stories, jokes etc
140115
Interstellar culture resolves disputes with simulated duels; antagonist cheats using telepathy
156430
black and white balls in the box
146101
Floating in a Dyson Sphere
106721
Short story about aliens trading for hydroponics
79207
YA novel about sister is alien with two hearts and assassins come
139475
story about an undercover agent investigating a super powerful games-playing human-like alien
51413
Protagonist becomes the avatar of an alien deity and has to cope with adversary god