Hey, It's That Sound!: In "Piece of My Heart", the Patterson's doorbell sound is the familiar "buzzer" one of the Pickles' residence in Rugrats.
Hey, It's That Voice!: This show features a number of easily recognizable voices, but one that really sticks out in two episodes, "The Wicked Game" and "Butterflies Are Free" with the inclusion of a minor character, the wacky evil bird-girl Polly Shuster, are instantly made hilarious when one recognizes who Carl's VA is.
Not only that, but consider that Carl's VA also appeared as Pau AND Alexandra in Dark Chronicle.
Keep Circulating the Tapes: Only two DVD's were released. One contains the special "Far From Home", the unaired pilot episode "The Party", and the series premiere "Ginger the Juvey". The other contains the finale "The Wedding Frame" and the episodes "Stealing First" and "Dare I, Darren?".
In 2013, the entire series was released on iTunes, including the unaired "high school" episodes. The series was also released on Amazon Instant Video the following year. Unfortunately, the episodes were removed from both services in January 2015 for unknown reasons. Two episodes which were once available in separate Nick-themed iTunes packs before the complete series release ("Ginger the Juvey" and "An Even-Steven Holiday Special") have been removed as well.
Most of the series can easily be found on YouTube uploaded by various fans of the series, albeit mostly in the form of low quality VHS recordings from Nick Australia in the mid-2000s, a couple of which have higher-pitched audio due to PAL speedup.
Missing Episode: In June 2004, Nickelodeon stopped airing new episodes after "Fair to Cloudy" ("Heat Lightning" was actually the last new episode to air in terms of actual air dates, but it comes before "Fair to Cloudy" chronologically) and released the series finale "The Wedding Frame" straight to DVD later that year, leaving all of the "high school" episodes unaired.
Nicktoons aired "Ten Chairs" once in November 2004 as part of a Thanksgiving marathon and finally aired the first high school episode "Stuff'll Kill Ya" (a Very Special Episode centered on caffeine addiction) at 7:30 AM in November 2006 with no fanfare. The rest of the episodes were initially lined up to air over the following days but were pulled at the last minute (Some Wikipedia edits claim that the last episodes aired in 2009, but this is not true).
Nicktoons' rerun rotation did not include "Sleep On It" or "Ginger's Solo". The former was also pulled from reruns from the regular Nickelodeon after a few years. It is unknown why they were pulled, although it may have been due to petty parental complaints (in the case of "Sleep On It", possibly over Hoodsey visibly wetting himself or the girls' comments on bedwetting being "disgusting"; in the case of "Ginger's Solo", possibly over Clover appearing very underdressed).
"The Right Stuff" and "Gym Class Confidential" were also pulled from the rerun rotation by 2007, probably for reasons that can be found on the Radar page, although at least the former was reinstated shortly before the show was ultimately removed from US television in January 2009, as a recording of this episode from circa 2008 exists online with a Nicktoons Network logo.
When the series was available for purchase on iTunes and Amazon from 2013-15, the episode "Detention" (the first of the unaired episodes) contained a few seconds of blatant "glitching" about five minutes in with very noticeable "sparks" appearing in the image and audio, virtually making the scene unwatchable (although it may be just a transfer error). "Sibling Revile-ry" from Season 2 also contained such "glitching", but only for about two seconds.
Subverted in Canada. Nick Canada currently airs the show on weekdays and they show all episodes in chronological order (with the exception of "An Even Steven Holiday Special", "April's Fools", and "The Easter Ham" due to being themed after holidays, as well as "Foutley's on Ice" AKA "Far From Home"). Nickelodeon US reran episodes in a random order and premiered many episodes out of order.
Playing Against Type: The usually dull and slow speaking Ben Stein as fast-talking realtor Buddy Baker.
What Could Have Been: The unaired pilot was quite different from the show we know of today. The main difference were the designs and art style. The hair styles were different, Miranda and Darren were white, and the style was similar to the Rugrats (Deranged Animation and all). Perhaps the biggest difference is Courtney being much much more of an Alpha Bitch, and Blake being an Annoying Younger Sibling and radically out of character compared to how he is in the show. (He crashed the party in his underpants!)
The pilot's since been uploaded here (though Darren looks more grey than white....).