There has been talk about this already, but in case anyone missed it:

The 2016 edition of Internet Problem Solving Contest is going to take place today (starting time).

It's a 5-hour contest for teams of up to 3 people, but there's also an individual division, so feel free to participate even if you can't find yourself a team at this point.

There's going to be an ACM-like number of problems (12+), ranging from classic algorithmic problems to quite unusual ones. Most problems have an easy subproblem worth 1 point and a hard one worth 2 points (think CodeJam); ties are broken using ACM rules (sum of times).

The practice session is running; it ends 2 hours before the contest! If you haven't competed before, it lets you get familiar with the contest system... and the problems there aren't completely trivial.

Read the rules or my previous blogposts about this for more info.

Belated, yet necessary warning!

Since this is a 5-hour contest where you can execute codes locally, some inputs will be YUGE (gigabytes). Accordingly, they will have fairly high system requirements. While the official solutions quite comfortably run on my mediocre laptop, if you write something too inefficient, you can encounter a nasty surprise, e.g. frozen system. It happened to me last year.

If an input is big, you won't have to download it; instead, there will be a generator (typically a Python script, meaning they aren't very fast). It's usually a good idea to run all generators as early as possible — as long as it doesn't slow down your computer too much, you can avoid a situation where you can't submit a problem because the contest ended before your generator.

Actually, you should just try to read as many problems as possible and determine your strategy after you can guess your chances well enough.