In the wake of the crash of 2008 and as a popular response to the Great Recession, a number of organizations have formed to gather concerned people who want the situation fixed. Many of these emerged online, or were outgrowths of single protest events, not always connected to established activist organizations.
This is a novel development - the internet protest movement - which is based not on institutions (at least not visible institutions) but around online organizations that bring together interested individuals. These are, at some level, media events, or perhaps more accurately, "new media" events.
This stands in contrast to the organizing developed in the post-WW2 era after the growth of unions in the 1930s and 1940s. The organizing of that time was more about forming community-based organizations. This was to bring middle-class style organizing to the poor in urban areas.
The largest online organizers of recent memory have been MoveOn.org, the various Tea Party groups, the Obama campaign's Organize for America, and flashmobs on YouTube.
The concept of online organizing is like an inversion of community organizing. With community organizing, you build a base, then take action. With online organizing, you invent the action first, then build the community of participants as the base.
One other thing that's interesting about online organizing is that it encourages multiple demonstrations rather than a single large demonstration. The value of this strategy is debatable. If an event can get only a few demonstrators, it makes the movement look weak.
The following websites have lists of actions happening on April 18th:
http://www.usuncut.org/ - US Uncut protests the austerity measures, and has activities from the 15th to the 18th. An LA event is here:
http://www.usuncut.org/actions/352 http://moveon.org - MoveOn has events planned for tax day. The theme is Tax Day Make Them Pay - to demand that corporate cheats who don't pay taxes pay up. There are a few events in LA. Search by zipcode here:
http://pol.moveon.org/event/events/index.html?action_id=242 http://www.coffeepartyusa.com/coffee-breaks-virtual - The Coffee Party USA is having a daily action involving making a phone call or taking a small personal action to protest the crap going on.
The War Tax Resisters League is not doing their own demo, but will be passing out information at other events.
http://www.nwtrcc.org/taxday2011.php http://www.marriageequality.org/ - Marriage Equality USA will be at the airport post office to call for an end to laws that prohibit same-sex marriage.
And, lastly, but not mentioned here but in jest are the Tea Party protests. These people are whacked out. They want to cut taxes, yet claim to worry about the national debt. The only way to pay that down debt is to simultaneously raise taxes and cut spending. I figured this out using a thing called "math."
Now, there is another way to pay it off more quickly: inflation. Steady inflation will erode the debt. And since the goal is to have little to no debt at all, it won't be a problem that demand for treasury bonds will dry up.