install.packages("Rcmdr", dependencies=TRUE)
library(Rcmdr)
...will also install and load nearly every other package you've ever needed to use (except ggplot2, Hmisc, and rms/design). This saved me a lot of time trying to remember which packages I normally use and installing them one at a time. Specifically, installing and loading Rcmdr will install the following packages from CRAN: fBasics, bitops, ellipse, mix, tweedie, gtools, gdata, caTools, Ecdat, scatterplot3d, ape, flexmix, gee, mclust, rmeta, statmod, cubature, kinship, gam, MCMCpack, tripack, akima, logspline, gplots, maxLik, miscTools, VGAM, sem, mlbench, randomForest, SparseM, kernlab, HSAUR, Formula, ineq, mlogit, np, plm, pscl, quantreg, ROCR, sampleSelection, systemfit, truncreg, urca, oz, fUtilities, fEcofin, RUnit, quadprog, mlmRev, MEMSS, coda, party, ipred, modeltools, e1071, vcd, AER, chron, DAAG, fCalendar, fSeries, fts, its, timeDate, timeSeries, tis, tseries, xts, foreach, DBI, RSQLite, mvtnorm, lme4, robustbase, mboost, coin, xtable, sandwich, zoo, strucchange, dynlm, biglm, rgl, relimp, multcomp, lmtest, leaps, effects, aplpack, abind, RODBC.
Anyone else have a solution for batch-installing packages you use on a new machine or fresh R installation? Leave it in the comments!