Despite the tragic start to the week, there was no shortage of excellent video material to keep us occupied while we fought long and hard to make it to Friday afternoon. Enjoy a selection of our favorite viral morsels from the past five days, including a moving tribute to Amy Winehouse by friend Mark Ronson. Because your weekend can't truly get started without it.

JUSTIN BIEBER JOINS SELENA GOMEZ ON STAGE FOR TIMBERLAKE COVER

The Bieb crashes his lady friend's show to sing "Cry Me A River." Hey, you know, we think there might be something going on between these two.

MARIAH CAREY'S HSN RAVINGS

Rich Juzwiak's observation of just how much Mimi loves selling jewelry—and presumably so much more—is the perfect poetic inspiration.

WATCH KATHY GRIFFIN'S KARAOKE COVER OF RIHANNA'S "S&M"

The funny lady is perfectly good at choosing potentially risky karaoke songs, and Rihanna approves!

OK GO'S NEWEST VIRAL VIDEO, "ALL IS NOT LOST"

The band gives us dancers, bodysuits, plexiglass and a split-screen in their newest clip. Yikes.

WATCH ADAM LEVINE AND STEVIE NICKS OUTDO "THE VOICE" WITH THEIR "LEATHER AND LACE" DUET

There’s also a Javier Colon duet or two. But, y’know, Stevie Nicks is a legend and Colon doesn’t even have an album out yet.

For singing LEGOs and star-studded holiday films, click NEXT.

MARK RONSON PAYS TRIBUTE TO AMY WINEHOUSE WITH "VALERIE"

“She is my sister, wherever she is,” says Winehouse's friend and collaborator during his first live performance following her death.

CONTINUE TO MOURN LCD SOUNDSYSTEM WITH A LEGO "ALL MY FRIENDS"

Another fan-made tribute clip that will have you missing the band all over again. (As if you ever stopped.)

"NEW YEAR'S EVE" TRAILER: LEA MICHELE SINGS, LUDACRIS SEDUCES

And if he didn’t even have to drop a line from “What’s Your Fantasy.” Go ahead and count the musicians in the trailer for the upcoming Hollywood holiday lovefest.

WATCH SELENA GOMEZ ASCEND TO BRITNEY-NESS WITH A SERIES OF COVERS

In which the current teen queen pays homage to the lady who did it first. Hey, they both dated people named Justin! We’re just saying.

BEYONCE ANNOUNCES NEW FAN VIDEO ON "THE VIEW," CONTINUES TO DAZZLE LIVE

B teaches Barbara Walters and Co. how to leave them wanting more with her "1+1" performance.

Don't forget to check out all of our video coverage here.