KNetFold is a software for predicting the consensus RNA secondary structure for a given alignment of nucleotide sequences. You can read about the scientific background of this software in the help document or in our recent publication.
The CyloFold web server is an option for predicting the secondary structure of single RNA sequences. For analyzing alignments of RNA sequences you also might want to try our 3D sequence logo generator called CorreLogo .
Bindewald, E and Shapiro B.A (2006): RNA secondary structure prediction from sequence alignments using a network of k-nearest neighbor classifiers. RNA. 12(3): 342-352 (2006).