October 5, 2007 - At the end of Season 2 of How I Met Your Mother, Ted (Josh Radnor) and Robin (Cobie Smulders) broke up. Given that Ted had been so very infatuated with Robin from the start of the series, it was understandable that he'd need some time to get over this, even if the break up was on good terms. However, after some ill-fated attempts at dating in the most recent episodes, things are beginning to look up for Ted on the third episode of the season, in a big, big way.

Called "Third Wheel," the episode follows what happens when Ted has a surprise reunion with Trudy (Danica McKellar), his one night stand from the Season 1 episode "The Pineapple Incident." Trudy climbed out of Ted's window and went down his fire escape at the end of that episode, never to be seen again… until now that is. Not only does Ted run into Trudy, but they both happen to run into Trudy's old college classmate Rachel, which is going to open the door to a very interesting opportunity for Ted. An opportunity to, as the characters on the episode put it, "ride the tricycle."

Visiting the set of this episode of How I Met Your Mother, I met Busy Philipps, who plays Rachel. Explaining Rachel's past with Trudy, Philipps said "Well we play sorority sisters who haven't seen each other in awhile and we run into each other at this bar. We were very competitive in the past, but now that's all behind us and now we're both sort of vying for Ted's affections. And then we come up with sort of a compromise I think on how to handle that situation… And it's whether or not Ted can hang, so to speak. It's really funny."

Philipps, who got her start on Freaks and Geeks, noted that she's a regular viewer of How I Met Your Mother, telling me "I'm friends with some of the people that are on the cast and I always like to support my friends so I TiVo all their shows. I don't know if that counts for anything, but it makes me feel good!" That being the case, Philipps said she was "really excited when they asked me to come on and do the show. I hadn't even read the script yet and I said yes, because I just wanted to work with my friends, and I knew the show was high quality enough that I would think it was funny."

Philipps was pretty surprised when she did finally read the script, saying her first reaction was "I can't believe they're doing this storyline! Frankly, I think it's a little racy. Maybe I'm prudish, but I think it's quite racy! I like the terminology they've come up with: 'the tricycle.' I'm really liking it. I've had a great time here and everyone's been, obviously, so nice."

McKellar of course grew up in the public eye, thanks to her iconic role as Winnie Cooper on The Wonder Years, but Philipps had a confession to make, saying "I don't want to come off as a total loser, but I wasn't a Wonder Years watcher when I was young. I don't know what happened! I sort of missed it."

McKellar, a math major at UCLA who then co-authored a scientific paper proving a theorem in mathematical physics (yeah, she's smarter than most of us), has recently written a very well-received book aimed at young girls called Math Doesn't Suck: How to Survive Middle-School Math Without Losing Your Mind or Breaking a Nail, and Philipps related how the two bonded talking about it. "Earlier we talked about math and her writing that book about math," said Philipps. "I was just saying to my husband that if we have kids, he's gonna have to do the math homework with them, because I've always been terrible at math and Danica was like 'No, that's what we have to change, right now!' So she convinced me to go get the book and brush up on my math skills. I have a few years, I think, before I have kids, so I have time to get really good at it."

While they unfortunately have no direct scenes together, How I Met Your Mother reunites Philipps with her former Freaks and Geeks costar Jason Segal, right on the heels of her just completed stint on E.R. with another Freaks alum, Linda Cardellini. Philipps remarked that "It's fun to work with all of my friends from Freaks and Geeks in whatever capacity, because I've had the opportunity over the last few years, since the show has been off the air, to work with several of these guys again and it just is such a special thing. I mean it sounds so cliché, but we really all still have a crazy bond. It's really nice. It's a really, really nice thing to have. And rare! I haven't had it since."