Inside the trolley car are a number of parody advertisements based on real products of the time, including Arrow collars ("Narrow Collars"), Smith Brothers cough drops ("Sniff Brothers Cough Drops") and Fisk Tires ("Risk Tires").
Both the Snork and Snork Maiden also appear, living with the Moomins, in the following book, Finn Family Moomintroll, but are not mentioned in The Exploits of Moominpappa, the events of which are solely related to Moomintroll, Snufkin and Sniff.
In the Futurama episode 3ACV11 "Insane in the Mainframe", Bender suggests that Fry retire on Tender Vittles after Fry loses his retirement fund on scratch and sniff lottery tickets.
Finn Family Moomintroll - This is the first appearance of the Groke, and she is generally played as a frightening villain, though Sniff expresses a bit of sympathy for her, at one point moving himself to tears with a speech on how awful it must be to be so alone.
Anyone within the geographical network range of an open, unencrypted wireless network can 'sniff' or capture and record the traffic, gain unauthorized access to internal network resources as well as to the internet, and then use the information and resources to perform disruptive or illegal acts.