Some say to publish blog can do the helps. But why must in 24 hours? It is good enough if you can get indexed in one week.
How To Get Included In The Google Index in 48 Hours or Less Not quite 24, but iv'e seen less than 48 hours before..
If you own a blog, then make sure it pings all the major services - and has a few links from other blogs, and bang, you'll get indexed in under 24 hours.
pr has nothing to do with spider activity. thare are pr4 pages that dont get spidered for over 2 weeks even a month.