Indico makes pretty reasonable .ics files if you know how to find them and if conveners can be bothered to keep events relatively categorized. Unfortunately most conveners have more important convening to do, so the indico index in any given category is usually a nightmare of events that no one cares about. That in turn means that subscribing to the category events.ics file is just adding noise to your calendar.

This is a script to help.

You can run it like

calcomb.py <url to events.ics file> [more urls...] -m <match 1> [match...]

Where it's very important that you include the URL with your user_token=* at the end. Hint: you can get the full url with the token by clicking the little calendar dohikcy on the upper right side of the indico category. The match field just matches the event summary, i.e. something like comb will match "SUSY + exotics global combination meeting", "thedotcombubble" etc.

You can combine as many URLs as you like, and then run as a cron job that dumps everything to another public URL. Then you can unsubscribe from those reminder emails and get some real work done.

You can also use Indico's export API to avoid creating a special token for each event and embedding that token in the call. The syntax is

calcomb.py <catigory id> [more ids] -k -m <match 1> [match...]

Note that you'll need a local file called ~/.indico-secret-key which should contain your indico credentials. It have the format

XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
YYYYYYYY-YYYY-YYYY-YYYY-YYYYYYYYYYYY

where first line is the token, second is the "secret".