If Congress does not come to an agreement, automatic across the board cuts will hit in January 2013. There are many dramatic effects in these cuts, but in my biased but I think well-founded view, none is more damaging to the long-term economic future of our country than cuts to research funding.
Overall, the sequester will result in 8.7% cut (or $12.5 billion) in federally-funded research. The estimated reduction in GDP in the next 10 years due to these cuts is between $200 billion to $860 billion (source).
Most of the growth the United States saw in the twentieth century is due to it being the world leader in scientific discovery and technological innovation. Decreasing funding to research (when it was supposed to be doubled) is absurdly irresponsible.