Now here's a clever trick. Inventive Labs Gadgets has designed a Safari bookmarklet that adds "tabs" to your iPhone browsing experience. Just drag their bookmarklet into your Safari bookmarks bar, then sync your iPhone or iPod touch. (Make sure you've selected Info > Web browser > Sync Safari bookmarks in iTunes.)
Once synced, open a web page and then choose Tabulate from your iPhone bookmarks list. A small orange icon appears at the top-left of the screen. Next, tap on any link. The three-button control window shown here appears.
Tap on blue to open the link in the current tab, green to open the link in a new tab (i.e. a new Safari page, in iPhone terms), and orange to add the link to the list of flagged links to open later. The flagged items appear in orange at the top-left of the screen.