Intel (obviously!) but most important for WIFI
HP - for Printers/Scanners/AIO... though ironically it is best to avoid their laptops due to UEFI weirdness
Samsung stuff generally plays nice
Generally the peripheral scene is much healthier (and simpler) for Linux than it has ever been!
A few to avoid like the plague include Broadcom (wifi/ethernet), DELL (frequently use Broadcom chips even when spec says Intel), Atheros and Realtek can be a bit hit n miss. Nvidia and ATI just can't make their bloody mind up whether they want to play with the big boys or not pmsl