Let’s talk merch.

Celebrities sell t-shirts, gym shoes, lotions and potions – all with their names attached in the hopes that you, me and everybody else buys into the merchandising madness. And it’s working. Some folk make more money off selling t-shirts than they do from selling concert tickets.

Beyonce’s genius move to create and sell “Boycott Beyonce” t-shirts are an example of how merch game works. She usurped a negative idea, flipped it on a shirt, embraced that narrative and now you can buy it for (most likely) upward of $25 during her concert tour. The shirts debuted at her Miami concert.

Chicago rapper Chief Keef once told me that merch is the way to destroy the game. He sporadically releases new music, and has plenty of enemies, yet continues to sell Glo Gang t-shirts at a dizzying pace. The gentleman who makes and sells said Glo Gang shirts says they pull a respectable $10,000 to $15,000 a month, easily, off the simple silk screened pieces of cotton. The markup is incredible, my source tells me.

According to The Fashion Law blog, concert merch is about to get even bigger. Prince merch in particular could be a big issue moving forward as the artist’s estate recently made moves to prevent unauthorized creation of all sorts of things in Princes name, including bathrobes. It’s not surprising that someone who is not related might try to cash in on Prince merch at their own event.

Posts the blog, in part: “Concert ‘merch’ has just become part of the multimedia experience and another way for really smart artists to continue to monetize their brands, as more people stream music and the music industry looks for other avenues to bring in revenue,” says Jian DeLeon, streetwear expert and senior menswear editor at WGSN.”

Birdman and his Respek shirts are another example of merch that works. They’re sold on Cash Money’s Merch Direct site. Those shirts cost upwards of $30 a pop and you can read all about them on our sister site Jet. They are selling like hotcakes yet anyone who has ever done a family reunion knows those shirts only cost between $3 and $5 to actually make. Again, the markup is incredible. And profitable.

Consider the San Francisco-based company Teespring, which you’ve probably seen advertised heavily on Facebook. That outfit has designers pulling in $100,000 a year off t-shirts with snarky sayings. Keep Calm and Carry On is one of them.

T-shirts are a cheap way to make millions. Sure they do it with perfume (J-Lo has 18 and counting) or by selling workout gear, a la Ivy Park and Beyonce. But t-shirts are like lipstick: not too pricey, not too much of an investment and an instant style statement.

Neither Beyonce nor Birdman’s people will disclose how much they earn from their respective t-shirt sales, but it’s sure to be enough to earn critic’s “respek.”

Adrienne Samuels Gibbs is a Chicago-based writer. Follow her @adriennewrites.