Re: want web-based aggregator that outputs RSS

["jdklub" <pseudonym@mindspring.com>]

sorry for the self-plug, but... fyuze.com may be your answer.

> 1) web-based service, to which I could go and create one or more 
> lists of RSS feeds to be aggregated, including arbitrary (i.e. 
> user-
> submitted) RSS URLs that I supply.

after you create an account, you can create as many "tabs" (lists) 
as you'd like. each tab can contain any number of feeds from any 
number of sources. you can arrange your chosen feeds into whatever 
two-dimensional configuration you'd like (ie, feeds can span columns 
as well as rows, allowing you to create a patchwork of RSS goodness)

you can select feeds from the directory, or input your own feed(s) 
URLs directly  (fyuze.com/customize), or use the "bookmarklet" to 
use auto-magically add feeds from sites you visit via RSS auto-
discovery.

> 2) for each RSS feed list, the service would (like Meerkat) 
> periodically check the feed for new stories, and add any new items 
> to 
> a single, reverse-chronological article list, while maintaining a 
> label to identify the item's source.

fyuze crawls through its list of feeds every 45 minutes. feeds can 
also ping fyuze to be updated in realtime (fyuze.com/api). your 
feeds are displayed in reverse chronological order. the number items 
displayed from each feed is configurable by you. you can specify 
either a number, say 10, or a time frame, last 24 hours. you can 
also choose whether or not to display descriptions (when available).
  
> 3) this resultant article feed is, itself, available as a web-
> accessible RSS feed. 

not sure why you would need this unless you wanted to move the 
compiled synthetic feed into another aggregator. fyuze used to 
support this, but no longer does. if you really wanted it, i could 
reactivate it.

> The service would be web-based (i.e., server-side) so that it 
> could 
> operate constantly, even if my own computer is off or offline.

check.

you can additionally create "search agents" that search all known 
RSS feeds for a particular word or phrase. (ie. you could create a 
search agent for "RSS").

accounts are free.