Ok, so a good site for flash games on the N900 is pickychicky.com. They have fullscreen links for most games.
Just wasted 5 minutes on "Bush Royal Rampage", these sniper games are great fun with cursor mode enabled - much easier to target with the touchscreen than using a mouse! Saved the queen
Unpack the ZIP file found via the post and place the "games" directory on your memory card. Open Games.html found in that directory with your tablets browser. Save that opened site as a "Favorite" and enjoy.
BTW, if the Browser options on the N900 are the same as the N8**'s, you can download SWF files you find with the MicroB browser directly to the device.
Simply turn off flash and when you browse back to the site with your intended prize, MicroB will now show a download place holder instead of running the Flash.
Download the SWF, re-enable Flash in in MicroB, click on the SWF file from the "File Manager" and rock on.