Quality R newbie packages that potential financial researchers and quant traders who model or build a strategy and algorithm

As a newbie to R, I thought it would be worthy to note a few quality R packages that seem to have more advanced some functionality that Matlab does not even give you. Here is my experience thus far:

RTAQ

This is a tough one to gauge as I have recently tried to get something working with this but will only work with New York Stock Exchange data. At first I thought you could easily download like in Yahoo Finance but I don’t think you can. It seems strange when there are two versions file of this trade and quote capture system.
xts

This seems to be a pretty popular way to convert market data into a time series data frame used throughout other financial R packages listed here.

quantstrat

Another sophisticated R package where you can combine with blotter is to apply different classic technical indicators to your market objects. You can apply indicators, signals, and rules using technical analysis indicators like MACD, RSI, and Bollinger Bands. You can even apply your own algorithm to these as well which leads into quant related type of modeling.

blotter

Another useful package for first round of testing within R. This can be at the core of many analytical trading systems with capabilities to capture end of day market data, set currency rate, and create portfolio, and accounts, and with sophisticated charting capabilities.
PerformanceAnalytics

This is easily one of the best R packages yet since it has some very decent charting capabilities you can find in popular trading platforms like Metatrader. You can easily add different type of charting lines to plots. It contains a great and easy way to extract different types of statistical and market data.

Other worthy R packages to mention include:

quantmod
lspm
PortfolioAnalytics

FinancialInstrument

TTR
signalextraction

I hope this helps those out new to the world of R