I have a few games, being that in my job I have alot of time to do nothing, if I enjoy playing a game and its only a couple of quid, to unlock a bunch more of its features, then im happy to pay for it.
Other useful apps that I have;
Antivirus: gotta be an essential - some will disagree, but your Galaxy Portal is, like many smart phones, essentially a mini PC with much the same core components. Although they run of different operating systems (symbian/windows mobile/android etc) it is still possible to infect a phone in theory, and im not going to rule out in practice too.
Barcode Scanner: Once installed you can use your phones camera to scan barcodes, to get the latest prices on products, or to transfer information like a business card using a QR Code (2D barcode)
RAC Traffic: Does what it says on the tin, needs access to your GPS, but will give you traffic alerts based on your location.
There are others that I use, but are just for personal preference, like Opera mini web browser, advanced task killer, hidenseek, and-explorer and open home.