Heres an easy way (well, easy for installing) to save images on your iphone when you are browsing the web with safari.
First:
add this source to your installer.app
http://repo.ispazio.net
then, install “safari addon features from the “ispazio apps” category
then, go to development category and install jiggy runtime.
then, install imgsaver from ispazio apps.
Its time to save images.
Go to safari, and find the image that you want to download. Click on your bookmarks, and choose “display all images”, then tap on the image that you want to save.
click the home button, and go to imgsaver, tap on import history, and you will see there the url of the image, tap on it, then tap again on save, and it will be sent to your “camera roll” (photos/cameraroll)
any questions? ask here.
Diego is a ParT-tIme BloGGer Who likEs to tAlk about tHE iphone In thiS blog. You Can fInd HIm hEre too: 
June 8th, 2008 at 4:17 am
Does this work on the itouch?
June 25th, 2008 at 2:16 pm
if this works on the itouch where do I go to find my pictures
July 7th, 2008 at 1:17 pm
Yes this works also on itouch, but you need another thing, look in installer and make a search for “itouch” look for something like “cameraroll for itouch” and install it. Now open photos, and there should be a new folder.
February 19th, 2009 at 9:52 am
I had this cool app before I upgraded my iPhone to
2.2.1. Can it still work because installer doesn’t have the App.What can I do?
February 21st, 2009 at 12:26 pm
in firmware 2.x you dont need this app. just let your thumb over the image for 4 seconds and a popup will appear with an option “save image” the image will be saved in your cameraroll.
May 28th, 2009 at 3:00 pm
I just got my itouch. I’ve always thought apple stuff was style over substance. Overpriced and poor, disguised by nice shiny interfaces and the fact that apple for some reason is ‘cool’.
The fucking thing cant even save images from its browser. Wtf? That is ridiculous. It’s a damn image. Pathetic. Why does everyone love apple so much?
October 12th, 2009 at 6:18 pm
Dean, CAALM DOWWN dear…you underestimate the power of Apple…just click App Store and search for websave…60p spent and there it is for good! Seperate browser from safari but exactly the same. Now apologise to Apple and enjoy your iTouch!