I do.

In fact I think homebrew is almost as important a reason to support a system as the official games.  I also think there are alot of people out there who would support homebrew if they knew how easy it is to run.
    If you have an old enough PSP you can play homebrew straight from your memory stick because Sony didn't require the code to be signed.  In newer versions of their firmware you have to abuse exploits. 
    If you have a DS you can trot right on down to Best Buy, and Pick up a Music 'n' Games by Datel, or a Max Media Dock also by Datel, The MMD has a few problems but the Newer MnG is much better.  Of course there are other flash carts out there but since they support the play of backup games they are illegal in the US at least.

    Other people may not use homebrew because they are under the impression that it is low quality.  Admittedly there are a lot of games out there in the homebrew scene that I could care less about.  But it is nice to be able to play a game like GO, chess, or mancala, which would never make a release as a full blown $20-40 dollar game.
    More important are the applications like Fileassistant++ for the PSP which lets me do everything that explorer does in windows, on my PSP with no need to hook up to a computer.  Or Wifi sniffer that lets me sniff wifi hot spots without booting up my laptop.  For the DS there are apps that let you chat with Voice over IP (Voip) as well as draw and type over the internet. Think Pictochat on steroids.  And Moonshell is a mighty fine Media player for the DS.  Plus calculators, calanders, and a host of other PIM functions.

    So go on, if you have a PSP Home brew is so easy for you to do.  And if you have a DS 40 bucks for a Devices that lest you play music and Movies, as well as homebrew isn't bad.  Think of it this way: $120+$40=$160 If you get a datel MnG that comes with a 128mb card, enough for some Home brew as well as space left over for an hours worth of MP3s.  You've still paid about a hundred dollars less than you would have for a PSP, and how you can do everything it can, plus you get to play the better line up of official games!

BTW a homebrew Web browser for the DS is under development as we speak.