Junk faxes may sound like a problem from the '90s — but they can still lead to large payouts for plaintiffs.

A Miami federal judge last week gave final approval to a $1.55 million nationwide class action settlement for thousands of schools that complained about receiving reams of unsolicited faxes advertising Gorilla Glides, felt pads that go underneath chairs and tables to protect floors.

The allegations came under the Telephone Consumer Protection Act, which also covers robocalls and spam text messages. Lawsuits under the TCPA have increased dramatically in recent years, with 44 TCPA lawsuits filed in 2009 and 4,860 filed last year, according to the Wall Street Journal. The law provides for recovery of up to $500 per fax.