It'd be possible, but it wouldn't be right. For that matter, I could do the same in nearly real-time by having a script hit their site every 30 seconds to get the same data. I've got bandwidth to spare.
Personally, I think a 15-20 minute delay is all I'd find acceptable and expect that most of the site's users would feel the same way.
http://finance.lycos.com/home/subs/qdp.asp may be just what I'm looking for. If I felt the increase in subscriptions (it'd definitely be subscriber-only) would offset the cost.
If I step into the quotes arena, I'd also be curious about how people would feel about something I wanted to see on SI, but we didn't do it: Affixing an optional "quote-stamp" to posts to show what the delayed price of the stock was at the time a post was submitted and keep it there.
Also, if I make this step (getting QDP or something similar, and doing the coding necessary to get quotes onto the site), then I'll have already taken most of the steps necessary to add portfolios to the site.
So it's really a bit of a dilemna for me. The businessman side of me doesn't want to spend the money (or my time) unless I feel good about the ROI. The old SysOp in me doesn't want to stray from being "just a message board". But the "old SysOp who's also into the market" wants very much to have quotes and portfolios right here where I'm reading/talking about the stocks.
On the flip side, though, when I was active in the markets and cared most about quotes, I always had QCharts running while I was posting. SI's quotes were meaningless to me and if I could've turned them off I would've. Now that I'm not as serious about the market, quotes on message boards are more meaningful to me.
In other words, when I would've been most inclined to have paid for membership to a market-related site, quotes on the site wouldn't have increased my likelihood of subscribing because I was already getting quotes, and now that I'm in a group where I would care about quotes on a message-board site, I also am not into the markets enough that I would be inclined to pay for membership to a site.
Granted, I'm not everyone, but I have to at least consider what the ROI would be like if everyone were (<shudder) like me.
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