Listen carefully to the dialog that ends "Rescue Bay". The group starts talking about syndication, and someone mentions Knight Rider, another David Hasselhoff production.
Mitch also mentions Knight Rider in "Sweet Dreams"; he asks a baby that he's babysitting if he wants to watch it.
Cast the Expert: Michael "Newmie" Newman, the only real lifeguard on the show (and likely one of the few actors who could actually swim like a pro.
Channel Hop: Debuted on NBC and lasted one season, then found a new life in syndication.
Dawson Casting: Nicole Eggert and David Charvet were both 20 when they began playing Summer and Matt, who were in high school at the start of syndicated season 2. Not too bad, but it still technically falls into this trope.
Jeff Garlin, for example, appears as a radio host in the episode "K-GAS". You may also recognize someone from Saved by the Bell and Showgirls amongst the cast during the start of syndicated Season 2 as well.
John O'Hurley, perhaps best known as J. Peterman on Seinfeld and the host of Family Feud from 2006-2010, plays a mentally disturbed man who is convinced his daughter is drowning in "Red Wind". In the same episode, famous talk show and news personality Geraldo Rivera guest stars as a guy who keeps picking a fight with Mitch because he thinks Mitch is trying to steal his wife.
Trevor Goddard, best known as Mic Brumby on JAG, plays an Aussie lifeguard on an excange program who's out for revenge on Mitch in "Fatal Exchange".
Kristina Wayborn, best known as Magda in Octopussy, plays a South African diamond smuggler in "Strangers Among Us".
Keep Circulating the Tapes: In America, at least, only the first three syndicated seasons are out on DVD (music edited, at that), along with a few NBC episodes as extras on the sets. The last season release was in 2007, so it's doubtful we'll get any more. The full series is out in Germany, though, and are frequently listed on Amazon.com; assuming you have a region free DVD player, those would be the way to go.
Hobie was first played by Brandon Call on the NBC episodes, then later by Jeremy Jackson in syndication.
The character of Neely Capshaw was played by three different actresses, believe it or not. The most famous one was Gena Lee Nolin, who portrayed her from syndicated seasons 6 to 8. But she was also played by Heather Campbell in her debut appearance, syndicated season 5's finale, "Wet and Wild". In syndicated season 9, Nolin was replaced by Jennifer Campbell.
Sleeper Hit: According to the executive producers, the pilot movie "Panic at Malibu Pier" was one of the few made-for-TV movies which actually got higher ratings in repeats than it did initially.
Write What You Know: A couple of the people working on the show, most notably co-creator and co-executive producer Gregory Bonann, were lifeguards in real life and used their experiences as plotlines on the show.
Richard Jaeckel played Mitch's old mentor who dies in the Pilot Movie; and starting in the 2nd season, Lieutenant (later Captain) Ben Edwards.
Nancy Valen had a small part in the Pilot Movie, many years before getting cast as Captain Samantha Thomas in the 7th season.
Jeff Altman first appears as a man on his honeymoon in "Lifeguards Can't Jump", but later appears as a completely different character, a Hollywood movie producer, in "Rescue Bay". He later appears in "Scorcher", playing secret service agent Dudley Dawson, and AGAIN in three 1998 episodes, playing medical supply salesman Ed Symes. Sure are a lot of guys running around L.A. that look exactly like the same man, aren't there?
Similarly, Jennifer Campbell first appeared as a biker named Jessie Majors in "Point Doom", before later being the third actress to portray Neely.
And Kelly Packard played two different girls on two separate two-parters (in 1991 and 1995) before landing the role of April in 1997.
Alexandra Paul returned in "Baywatch: Hawaiian Wedding", but not as Stephanie (for obvious reasons).